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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 10 |
| 5 | 20 |
| 6 | 58 |
| 7 | 129 |
| 8 | 466 |
| 9 | 1144 |
| 10 | 3828 |
| 11 | 10104 |
| 12 | 37281 |
| 13 | 101810 |
| 14 | 369043 |
| 15 | 1061567 |
| 16 | 3973614 |
| 17 | 11649570 |
| 18 | 44090410 |
| 19 | 133431028 |
| 20 | 508513935 |
| 21 | 1566776842 |
| 22 | 6059123603 |
| 23 | 19007334896 |
| 24 | 73793026201 |
| 25 | 235333880634 |
| 26 | 921738292786 |
| 27 | 2975020974513 |
| 28 | 11720384280152 |
| 29 | 38315348976215 |
| 30 | 151639320458975 |
| 31 | 500740054300233 |
[1,1,2,3,10,20,58,129,466,1144,3828,10104,37281, 101810,369043,1061567,3973614,11649570,44090410, 133431028,508513935,1566776842,6059123603, 19007334896,73793026201,235333880634,921738292786, 2975020974513,11720384280152,38315348976215, 151639320458975,500740054300233] |