| 1 | C31×#3060 | C2 | 1 | 1 | yes | maximal, characteristic |
| 2 | C31×#2115 | C2 | 1 | 1 | yes | maximal, characteristic, complemented |
| 3 | C31×#1812 | C2 | 1 | 1 | yes | maximal, characteristic, complemented |
| 4 | C31×#1340 | C2 | 1 | 2 | yes | maximal, complemented |
| 5 | C31×#1339 | C2 | 1 | 2 | yes | maximal, complemented |
| 6 | C2×C31×#135 | C4 | 1 | 1 | yes | characteristic, complemented |
| 7 | C2×C31×#131 | C22 | 1 | 1 | yes | characteristic |
| 8 | C31×#537 | — | 2 | 1 | no | — |
| 9 | C2×C31×M32 | — | 2 | 1 | no | — |
| 10 | C31×#470 | C4 | 1 | 1 | yes | characteristic, complemented |
| 11 | C31×#470 | C22 | 1 | 1 | yes | characteristic |
| 12 | C31×#469 | C4 | 1 | 1 | yes | characteristic, complemented |
| 13 | C31×#469 | C22 | 1 | 1 | yes | characteristic |
| 14 | C31×#465 | — | 2 | 1 | no | — |
| 15 | C31×#465 | — | 2 | 1 | no | — |
| 16 | C31×#427 | — | 2 | 1 | no | — |
| 17 | C2×C31×#106 | C4 | 1 | 1 | yes | characteristic, complemented |
| 18 | C31×#417 | — | 2 | 1 | no | — |
| 19 | C31×#410 | — | 2 | 1 | no | — |
| 20 | C31×#349 | — | 2 | 1 | no | — |
| 21 | C31×#349 | C22 | 1 | 2 | yes | — |
| 22 | C31×H(3,ℤ/4) | C22 | 1 | 2 | yes | — |
| 23 | C2×#41×C31 | — | 2 | 1 | no | — |
| 24 | C2×#41×C31 | D4 | 1 | 1 | yes | characteristic |
| 25 | C31×#135 | — | 4 | 1 | no | — |
| 26 | C31×#135 | — | 4 | 1 | no | — |
| 27 | C2×Q16×C31 | C2×C4 | 1 | 1 | yes | characteristic |
| 28 | C2×SD16×C31 | — | 2 | 1 | no | — |
| 29 | C2×D8×C31 | C2×C4 | 1 | 1 | yes | characteristic |
| 30 | C31×#131 | — | 4 | 1 | no | — |
| 31 | C31×#131 | — | 4 | 1 | no | — |
| 32 | C2×M16×C31 | C2×C4 | 1 | 1 | yes | characteristic |
| 33 | C2×M16×C31 | D4 | 1 | 1 | yes | characteristic |
| 34 | C2×M16×C31 | C23 | 1 | 1 | yes | characteristic |
| 35 | C22×C8×C31 | C2×C4 | 1 | 1 | yes | characteristic |
| 36 | C22×C8×C31 | D4 | 1 | 1 | yes | characteristic |
| 37 | C22×C8×C31 | D4 | 1 | 1 | yes | characteristic |
| 38 | C31×C22⋊Q8 | — | 2 | 1 | no | — |
| 39 | C31×C22⋊Q8 | — | 2 | 1 | no | — |
| 40 | C31×C22⋊Q8 | — | 4 | 1 | no | — |
| 41 | C31×#121 | — | 2 | 1 | no | — |
| 42 | C31×#121 | — | 2 | 1 | no | — |
| 43 | C31×#121 | — | 4 | 1 | no | — |
| 44 | C31×#121 | — | 4 | 1 | no | — |
| 45 | C31×#121 | — | 4 | 1 | no | — |
| 46 | C31×#117 | — | 2 | 2 | no | — |
| 47 | C2×C4⋊C4×C31 | — | 2 | 1 | no | — |
| 48 | C31×M32 | — | 2 | 2 | no | — |
| 49 | C31×M32 | — | 4 | 1 | no | — |
| 50 | C2×C16×C31 | — | 4 | 1 | no | — |
| 51 | C31×#107 | — | 4 | 1 | no | — |
| 52 | C31×#106 | — | 2 | 1 | no | — |
| 53 | C31×#106 | — | 4 | 1 | no | — |
| 54 | C31×#106 | C2×C4 | 1 | 1 | yes | characteristic |
| 55 | C31×#106 | C2×C4 | 1 | 1 | yes | characteristic |
| 56 | C31×#103 | — | 2 | 1 | no | — |
| 57 | C31×#103 | — | 2 | 1 | no | — |
| 58 | C31×#102 | — | 2 | 1 | no | — |
| 59 | C31×#102 | — | 2 | 1 | no | — |
| 60 | C31×#99 | — | 4 | 1 | no | — |
| 61 | C31×#99 | — | 4 | 1 | no | — |
| 62 | #41×C31 | — | 4 | 1 | no | — |
| 63 | #41×C31 | — | 4 | 1 | no | — |
| 64 | #41×C31 | — | 4 | 2 | no | — |
| 65 | #41×C31 | — | 4 | 2 | no | — |
| 66 | C2×Q8×C31 | — | 2 | 1 | no | — |
| 67 | C2×Q8×C31 | SD16 | 1 | 1 | yes | characteristic |
| 68 | C2×D4×C31 | — | 2 | 1 | no | — |
| 69 | C2×D4×C31 | — | 4 | 1 | no | — |
| 70 | C2×D4×C31 | — | 4 | 1 | no | — |
| 71 | C2×D4×C31 | — | 4 | 1 | no | — |
| 72 | C2×D4×C31 | D8 | 1 | 1 | yes | characteristic |
| 73 | C2×D4×C31 | D8 | 1 | 1 | yes | characteristic |
| 74 | C2×D4×C31 | SD16 | 1 | 1 | yes | characteristic |
| 75 | C22×C4×C31 | — | 4 | 1 | no | — |
| 76 | C22×C4×C31 | — | 4 | 1 | no | — |
| 77 | C22×C4×C31 | C22⋊C4 | 1 | 1 | yes | characteristic |
| 78 | C22×C4×C31 | C22⋊C4 | 1 | 1 | yes | characteristic |
| 79 | C22×C4×C31 | C2×D4 | 1 | 1 | yes | characteristic |
| 80 | Q16×C31 | — | 4 | 1 | no | — |
| 81 | SD16×C31 | — | 4 | 1 | no | — |
| 82 | SD16×C31 | — | 4 | 1 | no | — |
| 83 | D8×C31 | — | 4 | 1 | no | — |
| 84 | M16×C31 | — | 4 | 1 | no | — |
| 85 | M16×C31 | — | 4 | 1 | no | — |
| 86 | M16×C31 | — | 4 | 1 | no | — |
| 87 | C2×C8×C31 | — | 2 | 1 | no | — |
| 88 | C2×C8×C31 | — | 2 | 1 | no | — |
| 89 | C2×C8×C31 | — | 2 | 1 | no | — |
| 90 | C2×C8×C31 | — | 2 | 1 | no | — |
| 91 | C2×C8×C31 | — | 2 | 1 | no | — |
| 92 | C2×C8×C31 | — | 2 | 1 | no | — |
| 93 | C2×C8×C31 | C22⋊C4 | 1 | 1 | yes | characteristic |
| 94 | C2×C8×C31 | C22⋊C4 | 1 | 1 | yes | characteristic |
| 95 | C2×C8×C31 | C22×C4 | 1 | 1 | yes | characteristic |
| 96 | C2×C8×C31 | C2×D4 | 1 | 1 | yes | characteristic |
| 97 | C4⋊C4×C31 | — | 2 | 1 | no | — |
| 98 | C4⋊C4×C31 | — | 2 | 1 | no | — |
| 99 | C4⋊C4×C31 | — | 4 | 2 | no | — |
| 100 | C4⋊C4×C31 | — | 4 | 1 | no | — |
| 101 | C4⋊C4×C31 | — | 4 | 1 | no | — |
| 102 | C4⋊C4×C31 | — | 4 | 1 | no | — |
| 103 | C22⋊C4×C31 | — | 4 | 1 | no | — |
| 104 | C22⋊C4×C31 | — | 4 | 1 | no | — |
| 105 | C22⋊C4×C31 | — | 4 | 1 | no | — |
| 106 | C22⋊C4×C31 | — | 4 | 1 | no | — |
| 107 | C22⋊C4×C31 | — | 4 | 2 | no | — |
| 108 | C42×C31 | — | 4 | 2 | no | — |
| 109 | C16×C31 | — | 4 | 2 | no | — |
| 110 | #11867 | C31 | 1 | 1 | yes | maximal, characteristic, direct product factor, Sylow |
| 111 | C23×C31 | — | 4 | 1 | no | — |
| 112 | C23×C31 | #102 | 1 | 1 | yes | characteristic |
| 113 | C23×C31 | #102 | 1 | 1 | yes | characteristic |
| 114 | C23×C31 | C2×D8 | 1 | 1 | yes | characteristic |
| 115 | Q8×C31 | — | 4 | 1 | no | — |
| 116 | Q8×C31 | — | 4 | 1 | no | — |
| 117 | Q8×C31 | — | 4 | 1 | no | — |
| 118 | D4×C31 | — | 4 | 1 | no | — |
| 119 | D4×C31 | — | 4 | 1 | no | — |
| 120 | D4×C31 | — | 4 | 1 | no | — |
| 121 | D4×C31 | — | 4 | 1 | no | — |
| 122 | D4×C31 | — | 4 | 1 | no | — |
| 123 | D4×C31 | — | 8 | 2 | no | — |
| 124 | D4×C31 | — | 16 | 1 | no | — |
| 125 | D4×C31 | — | 16 | 1 | no | — |
| 126 | C2×C4×C31 | — | 2 | 1 | no | — |
| 127 | C2×C4×C31 | — | 2 | 1 | no | — |
| 128 | C2×C4×C31 | — | 2 | 1 | no | — |
| 129 | C2×C4×C31 | — | 2 | 1 | no | — |
| 130 | C2×C4×C31 | — | 2 | 1 | no | — |
| 131 | C2×C4×C31 | — | 2 | 1 | no | — |
| 132 | C2×C4×C31 | — | 4 | 1 | no | — |
| 133 | C2×C4×C31 | — | 4 | 1 | no | — |
| 134 | C2×C4×C31 | — | 4 | 1 | no | — |
| 135 | C2×C4×C31 | — | 8 | 2 | no | — |
| 136 | C2×C4×C31 | — | 8 | 2 | no | — |
| 137 | C2×C4×C31 | — | 16 | 1 | no | — |
| 138 | C2×C4×C31 | #102 | 1 | 1 | yes | characteristic |
| 139 | C2×C4×C31 | #102 | 1 | 1 | yes | characteristic |
| 140 | C2×C4×C31 | C2×C22⋊C4 | 1 | 1 | yes | characteristic |
| 141 | C2×C4×C31 | C2×SD16 | 1 | 1 | yes | characteristic |
| 142 | C8×C31 | — | 2 | 1 | no | — |
| 143 | C8×C31 | — | 2 | 1 | no | — |
| 144 | C8×C31 | — | 2 | 1 | no | — |
| 145 | C8×C31 | #99 | 1 | 1 | yes | characteristic |
| 146 | C8×C31 | #99 | 1 | 1 | yes | characteristic |
| 147 | #3060 | C2×C31 | 1 | 1 | yes | characteristic |
| 148 | #2115 | C2×C31 | 1 | 1 | yes | characteristic, complemented |
| 149 | #1812 | C2×C31 | 1 | 1 | yes | characteristic, complemented |
| 150 | #1340 | C2×C31 | 1 | 2 | yes | complemented |
| 151 | #1339 | C2×C31 | 1 | 2 | yes | complemented |
| 152 | C22×C31 | — | 2 | 1 | no | — |
| 153 | C22×C31 | — | 2 | 1 | no | — |
| 154 | C22×C31 | — | 2 | 1 | no | — |
| 155 | C22×C31 | — | 4 | 1 | no | — |
| 156 | C22×C31 | — | 4 | 1 | no | — |
| 157 | C22×C31 | — | 4 | 1 | no | — |
| 158 | C22×C31 | — | 8 | 1 | no | — |
| 159 | C22×C31 | — | 8 | 1 | no | — |
| 160 | C22×C31 | — | 8 | 1 | no | — |
| 161 | C22×C31 | C2×#102 | 1 | 1 | yes | characteristic |
| 162 | C4×C31 | — | 2 | 1 | no | — |
| 163 | C4×C31 | — | 2 | 1 | no | — |
| 164 | C4×C31 | — | 2 | 1 | no | — |
| 165 | C4×C31 | — | 8 | 1 | no | — |
| 166 | C4×C31 | — | 8 | 1 | no | — |
| 167 | C4×C31 | — | 8 | 1 | no | — |
| 168 | C4×C31 | — | 16 | 2 | no | — |
| 169 | C4×C31 | C2×#99 | 1 | 1 | yes | characteristic |
| 170 | C4×C31 | #421 | 1 | 1 | yes | characteristic |
| 171 | C2×#135 | C4×C31 | 1 | 1 | yes | characteristic, complemented |
| 172 | C2×#131 | C22×C31 | 1 | 1 | yes | characteristic |
| 173 | #537 | — | 2 | 1 | no | — |
| 174 | C2×M32 | — | 2 | 1 | no | — |
| 175 | #470 | C4×C31 | 1 | 1 | yes | characteristic, complemented |
| 176 | #470 | C22×C31 | 1 | 1 | yes | characteristic |
| 177 | #469 | C4×C31 | 1 | 1 | yes | characteristic, complemented |
| 178 | #469 | C22×C31 | 1 | 1 | yes | characteristic |
| 179 | #465 | — | 2 | 1 | no | — |
| 180 | #465 | — | 2 | 1 | no | — |
| 181 | #427 | — | 2 | 1 | no | — |
| 182 | C2×#106 | C4×C31 | 1 | 1 | yes | characteristic, complemented |
| 183 | #417 | — | 2 | 1 | no | — |
| 184 | #410 | — | 2 | 1 | no | — |
| 185 | #349 | — | 2 | 1 | no | — |
| 186 | #349 | C22×C31 | 1 | 2 | yes | — |
| 187 | H(3,ℤ/4) | C22×C31 | 1 | 2 | yes | — |
| 188 | C2×C31 | — | 2 | 1 | no | — |
| 189 | C2×C31 | — | 4 | 1 | no | — |
| 190 | C2×C31 | — | 4 | 1 | no | — |
| 191 | C2×C31 | — | 4 | 1 | no | — |
| 192 | C2×C31 | — | 16 | 1 | no | — |
| 193 | C2×C31 | #1519 | 1 | 1 | yes | characteristic |
| 194 | C2×#41 | — | 2 | 1 | no | — |
| 195 | C2×#41 | D4×C31 | 1 | 1 | yes | characteristic |
| 196 | #135 | — | 4 | 1 | no | — |
| 197 | #135 | — | 4 | 1 | no | — |
| 198 | C2×Q16 | C2×C4×C31 | 1 | 1 | yes | characteristic |
| 199 | C2×SD16 | — | 2 | 1 | no | — |
| 200 | C2×D8 | C2×C4×C31 | 1 | 1 | yes | characteristic |
| 201 | #131 | — | 4 | 1 | no | — |
| 202 | #131 | — | 4 | 1 | no | — |
| 203 | C2×M16 | C2×C4×C31 | 1 | 1 | yes | characteristic |
| 204 | C2×M16 | D4×C31 | 1 | 1 | yes | characteristic |
| 205 | C2×M16 | C23×C31 | 1 | 1 | yes | characteristic |
| 206 | C22×C8 | C2×C4×C31 | 1 | 1 | yes | characteristic |
| 207 | C22×C8 | D4×C31 | 1 | 1 | yes | characteristic |
| 208 | C22×C8 | D4×C31 | 1 | 1 | yes | characteristic |
| 209 | C22⋊Q8 | — | 2 | 1 | no | — |
| 210 | C22⋊Q8 | — | 2 | 1 | no | — |
| 211 | C22⋊Q8 | — | 4 | 1 | no | — |
| 212 | #121 | — | 2 | 1 | no | — |
| 213 | #121 | — | 2 | 1 | no | — |
| 214 | #121 | — | 4 | 1 | no | — |
| 215 | #121 | — | 4 | 1 | no | — |
| 216 | #121 | — | 4 | 1 | no | — |
| 217 | #117 | — | 2 | 2 | no | — |
| 218 | C2×C4⋊C4 | — | 2 | 1 | no | — |
| 219 | M32 | — | 2 | 2 | no | — |
| 220 | M32 | — | 4 | 1 | no | — |
| 221 | C2×C16 | — | 4 | 1 | no | — |
| 222 | #107 | — | 4 | 1 | no | — |
| 223 | #106 | — | 2 | 1 | no | — |
| 224 | #106 | — | 4 | 1 | no | — |
| 225 | #106 | C2×C4×C31 | 1 | 1 | yes | characteristic |
| 226 | #106 | C2×C4×C31 | 1 | 1 | yes | characteristic |
| 227 | #103 | — | 2 | 1 | no | — |
| 228 | #103 | — | 2 | 1 | no | — |
| 229 | #102 | — | 2 | 1 | no | — |
| 230 | #102 | — | 2 | 1 | no | — |
| 231 | #99 | — | 4 | 1 | no | — |
| 232 | #99 | — | 4 | 1 | no | — |
| 233 | C31 | #11867 | 1 | 1 | yes | characteristic, direct product factor, Sylow |
| 234 | #41 | — | 4 | 1 | no | — |
| 235 | #41 | — | 4 | 1 | no | — |
| 236 | #41 | — | 4 | 2 | no | — |
| 237 | #41 | — | 4 | 2 | no | — |
| 238 | C2×Q8 | — | 2 | 1 | no | — |
| 239 | C2×Q8 | SD16×C31 | 1 | 1 | yes | characteristic |
| 240 | C2×D4 | — | 2 | 1 | no | — |
| 241 | C2×D4 | — | 4 | 1 | no | — |
| 242 | C2×D4 | — | 4 | 1 | no | — |
| 243 | C2×D4 | — | 4 | 1 | no | — |
| 244 | C2×D4 | D8×C31 | 1 | 1 | yes | characteristic |
| 245 | C2×D4 | D8×C31 | 1 | 1 | yes | characteristic |
| 246 | C2×D4 | SD16×C31 | 1 | 1 | yes | characteristic |
| 247 | C22×C4 | — | 4 | 1 | no | — |
| 248 | C22×C4 | — | 4 | 1 | no | — |
| 249 | C22×C4 | C22⋊C4×C31 | 1 | 1 | yes | characteristic |
| 250 | C22×C4 | C22⋊C4×C31 | 1 | 1 | yes | characteristic |
| 251 | C22×C4 | C2×D4×C31 | 1 | 1 | yes | characteristic |
| 252 | Q16 | — | 4 | 1 | no | — |
| 253 | SD16 | — | 4 | 1 | no | — |
| 254 | SD16 | — | 4 | 1 | no | — |
| 255 | D8 | — | 4 | 1 | no | — |
| 256 | M16 | — | 4 | 1 | no | — |
| 257 | M16 | — | 4 | 1 | no | — |
| 258 | M16 | — | 4 | 1 | no | — |
| 259 | C2×C8 | — | 2 | 1 | no | — |
| 260 | C2×C8 | — | 2 | 1 | no | — |
| 261 | C2×C8 | — | 2 | 1 | no | — |
| 262 | C2×C8 | — | 2 | 1 | no | — |
| 263 | C2×C8 | — | 2 | 1 | no | — |
| 264 | C2×C8 | — | 2 | 1 | no | — |
| 265 | C2×C8 | C22⋊C4×C31 | 1 | 1 | yes | characteristic |
| 266 | C2×C8 | C22⋊C4×C31 | 1 | 1 | yes | characteristic |
| 267 | C2×C8 | C22×C4×C31 | 1 | 1 | yes | characteristic |
| 268 | C2×C8 | C2×D4×C31 | 1 | 1 | yes | characteristic |
| 269 | C4⋊C4 | — | 2 | 1 | no | — |
| 270 | C4⋊C4 | — | 2 | 1 | no | — |
| 271 | C4⋊C4 | — | 4 | 2 | no | — |
| 272 | C4⋊C4 | — | 4 | 1 | no | — |
| 273 | C4⋊C4 | — | 4 | 1 | no | — |
| 274 | C4⋊C4 | — | 4 | 1 | no | — |
| 275 | C22⋊C4 | — | 4 | 1 | no | — |
| 276 | C22⋊C4 | — | 4 | 1 | no | — |
| 277 | C22⋊C4 | — | 4 | 1 | no | — |
| 278 | C22⋊C4 | — | 4 | 1 | no | — |
| 279 | C22⋊C4 | — | 4 | 2 | no | — |
| 280 | C42 | — | 4 | 2 | no | — |
| 281 | C16 | — | 4 | 2 | no | — |
| 282 | C23 | — | 4 | 1 | no | — |
| 283 | C23 | C31×#102 | 1 | 1 | yes | characteristic |
| 284 | C23 | C31×#102 | 1 | 1 | yes | characteristic |
| 285 | C23 | C2×D8×C31 | 1 | 1 | yes | characteristic |
| 286 | Q8 | — | 4 | 1 | no | — |
| 287 | Q8 | — | 4 | 1 | no | — |
| 288 | Q8 | — | 4 | 1 | no | — |
| 289 | D4 | — | 4 | 1 | no | — |
| 290 | D4 | — | 4 | 1 | no | — |
| 291 | D4 | — | 4 | 1 | no | — |
| 292 | D4 | — | 4 | 1 | no | — |
| 293 | D4 | — | 4 | 1 | no | — |
| 294 | D4 | — | 8 | 2 | no | — |
| 295 | D4 | — | 16 | 1 | no | — |
| 296 | D4 | — | 16 | 1 | no | — |
| 297 | C2×C4 | — | 2 | 1 | no | — |
| 298 | C2×C4 | — | 2 | 1 | no | — |
| 299 | C2×C4 | — | 2 | 1 | no | — |
| 300 | C2×C4 | — | 2 | 1 | no | — |
| 301 | C2×C4 | — | 2 | 1 | no | — |
| 302 | C2×C4 | — | 2 | 1 | no | — |
| 303 | C2×C4 | — | 4 | 1 | no | — |
| 304 | C2×C4 | — | 4 | 1 | no | — |
| 305 | C2×C4 | — | 4 | 1 | no | — |
| 306 | C2×C4 | — | 8 | 2 | no | — |
| 307 | C2×C4 | — | 8 | 2 | no | — |
| 308 | C2×C4 | — | 16 | 1 | no | — |
| 309 | C2×C4 | C31×#102 | 1 | 1 | yes | characteristic |
| 310 | C2×C4 | C31×#102 | 1 | 1 | yes | characteristic |
| 311 | C2×C4 | C2×C22⋊C4×C31 | 1 | 1 | yes | characteristic |
| 312 | C2×C4 | C2×SD16×C31 | 1 | 1 | yes | characteristic |
| 313 | C8 | — | 2 | 1 | no | — |
| 314 | C8 | — | 2 | 1 | no | — |
| 315 | C8 | — | 2 | 1 | no | — |
| 316 | C8 | C31×#99 | 1 | 1 | yes | characteristic |
| 317 | C8 | C31×#99 | 1 | 1 | yes | characteristic |
| 318 | C22 | — | 2 | 1 | no | — |
| 319 | C22 | — | 2 | 1 | no | — |
| 320 | C22 | — | 2 | 1 | no | — |
| 321 | C22 | — | 4 | 1 | no | — |
| 322 | C22 | — | 4 | 1 | no | — |
| 323 | C22 | — | 4 | 1 | no | — |
| 324 | C22 | — | 8 | 1 | no | — |
| 325 | C22 | — | 8 | 1 | no | — |
| 326 | C22 | — | 8 | 1 | no | — |
| 327 | C22 | C2×C31×#102 | 1 | 1 | yes | characteristic |
| 328 | C4 | — | 2 | 1 | no | — |
| 329 | C4 | — | 2 | 1 | no | — |
| 330 | C4 | — | 2 | 1 | no | — |
| 331 | C4 | — | 8 | 1 | no | — |
| 332 | C4 | — | 8 | 1 | no | — |
| 333 | C4 | — | 8 | 1 | no | — |
| 334 | C4 | — | 16 | 2 | no | — |
| 335 | C4 | C2×C31×#99 | 1 | 1 | yes | characteristic |
| 336 | C4 | C31×#421 | 1 | 1 | yes | characteristic |
| 337 | C2 | — | 2 | 1 | no | — |
| 338 | C2 | — | 4 | 1 | no | — |
| 339 | C2 | — | 4 | 1 | no | — |
| 340 | C2 | — | 4 | 1 | no | — |
| 341 | C2 | — | 16 | 1 | no | — |
| 342 | C2 | C31×#1519 | 1 | 1 | yes | characteristic |
Finite Group Databasebeta