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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 7 |
| 5 | 18 |
| 6 | 53 |
| 7 | 188 |
| 8 | 799 |
| 9 | 4001 |
| 10 | 24050 |
| 11 | 179248 |
| 12 | 1639637 |
| 13 | 17764040 |
| 14 | 227653634 |
| 15 | 3550628492 |
| 16 | 67513114323 |
| 17 | 1519274903363 |
| 18 | 40153164845377 |
| 19 | 1278514703044023 |
| 20 | 49536414234360980 |
| 21 | 2279497269454146657 |
| 22 | 122986833567853232448 |
| 23 | 7942922462379370617039 |
| 24 | 622994706862172074402587 |
| 25 | 58218522316121110190816538 |
| 26 | 6379893924028925326363565894 |
[1,1,1,3,7,18,53,188,799,4001,24050,179248, 1639637,17764040,227653634,3550628492,67513114323, 1519274903363,40153164845377,1278514703044023, 49536414234360980,2279497269454146657, 122986833567853232448,7942922462379370617039, 622994706862172074402587, 58218522316121110190816538, 6379893924028925326363565894] |