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| n | a(n) |
|---|---|
| 0 | 2 |
| 1 | 5 |
| 2 | 13 |
| 3 | 35 |
| 4 | 91 |
| 5 | 241 |
| 6 | 631 |
| 7 | 1662 |
| 8 | 4362 |
| 9 | 11470 |
| 10 | 30127 |
| 11 | 79179 |
| 12 | 208023 |
| 13 | 546633 |
| 14 | 1436257 |
| 15 | 3773939 |
| 16 | 9916134 |
| 17 | 26055432 |
| 18 | 68461966 |
| 19 | 179888381 |
| 20 | 472667065 |
| 21 | 1241962303 |
| 22 | 3263330095 |
| 23 | 8574599917 |
| 24 | 22530279167 |
| 25 | 59199680826 |
| 26 | 155550750026 |
| 27 | 408719050346 |
| 28 | 1073934109927 |
[2,5,13,35,91,241,631,1662,4362,11470,30127,79179, 208023,546633,1436257,3773939,9916134,26055432, 68461966,179888381,472667065,1241962303, 3263330095,8574599917,22530279167,59199680826, 155550750026,408719050346,1073934109927] |