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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 21 |
| 5 | 249 |
| 6 | 4265 |
| 7 | 96773 |
| 8 | 2759229 |
| 9 | 95447863 |
| 10 | 3906844257 |
| 11 | 185703476509 |
| 12 | 10101591706057 |
| 13 | 621466309755017 |
| 14 | 42823493907501689 |
| 15 | 3278179258815893143 |
| 16 | 276843784084034075045 |
| 17 | 25636587602145118330341 |
| 18 | 2589449871609662090384097 |
| 19 | 283950074290110976428751741 |
[1,1,3,21,249,4265,96773,2759229,95447863, 3906844257,185703476509,10101591706057, 621466309755017,42823493907501689, 3278179258815893143,276843784084034075045, 25636587602145118330341,2589449871609662090384097, 283950074290110976428751741] |