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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 7 |
| 3 | 24 |
| 4 | 102 |
| 5 | 411 |
| 6 | 1835 |
| 7 | 7893 |
| 8 | 36351 |
| 9 | 162548 |
| 10 | 762138 |
| 11 | 3491511 |
| 12 | 16564826 |
| 13 | 77136405 |
| 14 | 369070850 |
| 15 | 1739073648 |
| 16 | 8372815451 |
| 17 | 39802063614 |
| 18 | 192546293264 |
| 19 | 921550475054 |
| 20 | 4474939591941 |
| 21 | 21533004329067 |
| 22 | 104880158196237 |
| 23 | 506865300408766 |
| 24 | 2474947871605487 |
| 25 | 12003534219048160 |
| 26 | 58733775050166893 |
| 27 | 285703983345337690 |
[1,2,7,24,102,411,1835,7893,36351,162548,762138, 3491511,16564826,77136405,369070850,1739073648, 8372815451,39802063614,192546293264,921550475054, 4474939591941,21533004329067,104880158196237, 506865300408766,2474947871605487, 12003534219048160,58733775050166893, 285703983345337690] |