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| n | a(n) |
|---|---|
| 3 | 1 |
| 4 | 2 |
| 5 | 5 |
| 6 | 15 |
| 7 | 46 |
| 8 | 139 |
| 9 | 449 |
| 10 | 1448 |
| 11 | 4799 |
| 12 | 15971 |
| 13 | 54107 |
| 14 | 184048 |
| 15 | 633365 |
| 16 | 2188644 |
| 17 | 7624153 |
| 18 | 26659774 |
| 19 | 93772014 |
| 20 | 330946542 |
| 21 | 1173233805 |
| 22 | 4171572088 |
| 23 | 14884905583 |
| 24 | 53249784377 |
| 25 | 191043396323 |
| 26 | 686956509123 |
| 27 | 2476044740337 |
| 28 | 8942288625630 |
| 29 | 32360306616473 |
| 30 | 117309644377341 |
[1,2,5,15,46,139,449,1448,4799,15971,54107,184048, 633365,2188644,7624153,26659774,93772014, 330946542,1173233805,4171572088,14884905583, 53249784377,191043396323,686956509123, 2476044740337,8942288625630,32360306616473, 117309644377341] |