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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 5 |
| 3 | 53 |
| 4 | 467 |
| 5 | 3913 |
| 6 | 32299 |
| 7 | 265353 |
| 8 | 2176758 |
| 9 | 17847997 |
| 10 | 146319703 |
| 11 | 1199485661 |
| 12 | 9832876386 |
| 13 | 80605364957 |
| 14 | 660764392260 |
| 15 | 5416629053076 |
| 16 | 44402915641056 |
| 17 | 363993693602517 |
| 18 | 2983844751876537 |
| 19 | 24460120087308763 |
| 20 | 200512266365651825 |
[0,5,53,467,3913,32299,265353,2176758,17847997, 146319703,1199485661,9832876386,80605364957, 660764392260,5416629053076,44402915641056, 363993693602517,2983844751876537, 24460120087308763,200512266365651825] |