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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 14 |
| 3 | 76 |
| 4 | 441 |
| 5 | 2652 |
| 6 | 16303 |
| 7 | 101727 |
| 8 | 641630 |
| 9 | 4080154 |
| 10 | 26112384 |
| 11 | 167978615 |
| 12 | 1085182436 |
| 13 | 7035477777 |
| 14 | 45750406205 |
| 15 | 298279844724 |
| 16 | 1949096816505 |
| 17 | 12761551428024 |
| 18 | 83701819019155 |
| 19 | 549850618355886 |
| 20 | 3617119500327536 |
| 21 | 23824816811652905 |
| 22 | 157106267803712709 |
[1,3,14,76,441,2652,16303,101727,641630,4080154, 26112384,167978615,1085182436,7035477777, 45750406205,298279844724,1949096816505, 12761551428024,83701819019155,549850618355886, 3617119500327536,23824816811652905, 157106267803712709] |