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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 9 |
| 3 | 22 |
| 4 | 51 |
| 5 | 111 |
| 6 | 233 |
| 7 | 474 |
| 8 | 942 |
| 9 | 1836 |
| 10 | 3522 |
| 11 | 6666 |
| 12 | 12473 |
| 13 | 23109 |
| 14 | 42447 |
| 15 | 77378 |
| 16 | 140109 |
| 17 | 252177 |
| 18 | 451441 |
| 19 | 804228 |
| 20 | 1426380 |
| 21 | 2519640 |
| 22 | 4434420 |
| 23 | 7777860 |
| 24 | 13599505 |
| 25 | 23709783 |
| 26 | 41225349 |
| 27 | 71501422 |
| 28 | 123723351 |
| 29 | 213619683 |
| 30 | 368080793 |
| 31 | 633011454 |
| 32 | 1086665562 |
| 33 | 1862264196 |
[1,3,9,22,51,111,233,474,942,1836,3522,6666,12473, 23109,42447,77378,140109,252177,451441,804228, 1426380,2519640,4434420,7777860,13599505,23709783, 41225349,71501422,123723351,213619683,368080793, 633011454,1086665562,1862264196] |