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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 6 |
| 5 | 20 |
| 6 | 141 |
| 7 | 260 |
| 8 | 1985 |
| 9 | 3887 |
| 10 | 124213 |
| 11 | 63013 |
| 12 | 2072737 |
| 13 | 4308063 |
| 14 | 72299423 |
| 15 | 19110234 |
| 16 | 1302089975 |
| 17 | 2789327371 |
| 18 | 192236392547 |
| 19 | 13000018109 |
| 20 | 3616336753079 |
| 21 | 7889633483913 |
| 22 | 138181586307115 |
| 23 | 37935218826111 |
| 24 | 2673839246416983 |
| 25 | 5905195803386319 |
| 26 | 209178924613512833 |
| 27 | 58019641542960071 |
| 28 | 4128415092111144721 |
| 29 | 9197893555411205235 |
| 30 | 164237433151443645047 |
| 31 | 11474995858629174895 |
| 32 | 3289139509736729288671 |
| 33 | 7376472520390786310211 |
| 34 | 1060236793997777905833443 |
| 35 | 74507380484700694744045 |
| 36 | 21473133267770763414163167 |
[1,1,2,6,20,141,260,1985,3887,124213,63013, 2072737,4308063,72299423,19110234,1302089975, 2789327371,192236392547,13000018109,3616336753079, 7889633483913,138181586307115,37935218826111, 2673839246416983,5905195803386319, 209178924613512833,58019641542960071, 4128415092111144721,9197893555411205235, 164237433151443645047,11474995858629174895, 3289139509736729288671,7376472520390786310211, 1060236793997777905833443,74507380484700694744045, 21473133267770763414163167] |