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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 10 |
| 5 | 23 |
| 6 | 62 |
| 7 | 153 |
| 8 | 433 |
| 9 | 1120 |
| 10 | 3281 |
| 11 | 8776 |
| 12 | 26399 |
| 13 | 72423 |
| 14 | 222496 |
| 15 | 622616 |
| 16 | 1946044 |
| 17 | 5533227 |
| 18 | 17545134 |
| 19 | 50545069 |
| 20 | 162237507 |
| 21 | 472541542 |
| 22 | 1532707268 |
| 23 | 4506042037 |
| 24 | 14748997812 |
| 25 | 43709690021 |
| 26 | 144213436887 |
| 27 | 430371626111 |
| 28 | 1429980808522 |
| 29 | 4293569179189 |
| 30 | 14355812667699 |
[1,1,2,4,10,23,62,153,433,1120,3281,8776,26399, 72423,222496,622616,1946044,5533227,17545134, 50545069,162237507,472541542,1532707268, 4506042037,14748997812,43709690021,144213436887, 430371626111,1429980808522,4293569179189, 14355812667699] |