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| n | a(n) |
|---|---|
| 1 | 10 |
| 2 | 40 |
| 3 | 114 |
| 4 | 426 |
| 5 | 1650 |
| 6 | 6126 |
| 7 | 23206 |
| 8 | 88636 |
| 9 | 337866 |
| 10 | 1295566 |
| 11 | 4992364 |
| 12 | 19269156 |
| 13 | 74529210 |
| 14 | 288954786 |
| 15 | 1122363984 |
| 16 | 4366362420 |
| 17 | 17011617426 |
| 18 | 66365823648 |
| 19 | 259213619826 |
| 20 | 1013542247970 |
| 21 | 3966939195402 |
| 22 | 15540399135516 |
| 23 | 60929935280508 |
[10,40,114,426,1650,6126,23206,88636,337866, 1295566,4992364,19269156,74529210,288954786, 1122363984,4366362420,17011617426,66365823648, 259213619826,1013542247970,3966939195402, 15540399135516,60929935280508] |