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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 72 |
| 5 | 149 |
| 6 | 221 |
| 7 | 370 |
| 8 | 21681 |
| 9 | 22051 |
| 10 | 43732 |
| 11 | 109515 |
| 12 | 1576942 |
| 13 | 3263399 |
| 14 | 4840341 |
| 15 | 8103740 |
| 16 | 474857261 |
| 17 | 482961001 |
| 18 | 957818262 |
| 19 | 2398597525 |
| 20 | 34538183612 |
| 21 | 71474964749 |
| 22 | 106013148361 |
| 23 | 177488113110 |
| 24 | 10400323708741 |
| 25 | 10577811821851 |
| 26 | 20978135530592 |
| 27 | 52534082883035 |
[1,1,2,5,72,149,221,370,21681,22051,43732,109515, 1576942,3263399,4840341,8103740,474857261, 482961001,957818262,2398597525,34538183612, 71474964749,106013148361,177488113110, 10400323708741,10577811821851,20978135530592, 52534082883035] |