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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 8 |
| 4 | 22 |
| 5 | 59 |
| 6 | 160 |
| 7 | 429 |
| 8 | 1155 |
| 9 | 3105 |
| 10 | 8354 |
| 11 | 22474 |
| 12 | 60457 |
| 13 | 162636 |
| 14 | 437509 |
| 15 | 1176941 |
| 16 | 3166097 |
| 17 | 8517138 |
| 18 | 22912002 |
| 19 | 61635707 |
| 20 | 165806564 |
| 21 | 446037175 |
| 22 | 1199887133 |
| 23 | 3227823181 |
| 24 | 8683185454 |
| 25 | 23358686444 |
| 26 | 62837334885 |
| 27 | 169039070970 |
| 28 | 454732963567 |
| 29 | 1223279724439 |
| 30 | 3290751724917 |
[1,1,3,8,22,59,160,429,1155,3105,8354,22474,60457, 162636,437509,1176941,3166097,8517138,22912002, 61635707,165806564,446037175,1199887133, 3227823181,8683185454,23358686444,62837334885, 169039070970,454732963567,1223279724439, 3290751724917] |