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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 8 |
| 4 | 23 |
| 5 | 64 |
| 6 | 160 |
| 7 | 397 |
| 8 | 968 |
| 9 | 2372 |
| 10 | 5714 |
| 11 | 13617 |
| 12 | 32007 |
| 13 | 74396 |
| 14 | 171222 |
| 15 | 390629 |
| 16 | 883922 |
| 17 | 1984631 |
| 18 | 4423528 |
| 19 | 9790146 |
| 20 | 21524829 |
| 21 | 47027558 |
| 22 | 102135967 |
| 23 | 220565018 |
| 24 | 473743833 |
| 25 | 1012274948 |
| 26 | 2152271718 |
| 27 | 4554344649 |
| 28 | 9593260912 |
| 29 | 20118418061 |
| 30 | 42012556671 |
| 31 | 87375161720 |
| 32 | 181001416773 |
[1,1,2,8,23,64,160,397,968,2372,5714,13617,32007, 74396,171222,390629,883922,1984631,4423528, 9790146,21524829,47027558,102135967,220565018, 473743833,1012274948,2152271718,4554344649, 9593260912,20118418061,42012556671,87375161720, 181001416773] |