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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 87 |
| 3 | 865 |
| 4 | 8354 |
| 5 | 71445 |
| 6 | 575062 |
| 7 | 4480480 |
| 8 | 33526931 |
| 9 | 246399359 |
| 10 | 1768719496 |
| 11 | 12506519769 |
| 12 | 87220471545 |
| 13 | 600957372469 |
| 14 | 4100864353926 |
| 15 | 27733540904781 |
| 16 | 186134535819880 |
| 17 | 1240811810649533 |
| 18 | 8221127809327654 |
| 19 | 54176483907555951 |
[0,87,865,8354,71445,575062,4480480,33526931, 246399359,1768719496,12506519769,87220471545, 600957372469,4100864353926,27733540904781, 186134535819880,1240811810649533,8221127809327654, 54176483907555951] |