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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 11 |
| 2 | 253 |
| 3 | 8855 |
| 4 | 416185 |
| 5 | 24554915 |
| 6 | 1743398965 |
| 7 | 144702114095 |
| 8 | 13746700839025 |
| 9 | 1470896989775675 |
| 10 | 175036741783305325 |
| 11 | 22929813173612997575 |
| 12 | 3278963283826658653225 |
| 13 | 508239308993132091249875 |
| 14 | 84875964601853059238729125 |
| 15 | 15192797663731697603732513375 |
[1,11,253,8855,416185,24554915,1743398965, 144702114095,13746700839025,1470896989775675, 175036741783305325,22929813173612997575, 3278963283826658653225,508239308993132091249875, 84875964601853059238729125, 15192797663731697603732513375] |