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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 10 |
| 2 | 35 |
| 3 | 140 |
| 4 | 645 |
| 5 | 3150 |
| 6 | 15655 |
| 7 | 78160 |
| 8 | 390665 |
| 9 | 1953170 |
| 10 | 9765675 |
| 11 | 48828180 |
| 12 | 244140685 |
| 13 | 1220703190 |
| 14 | 6103515695 |
| 15 | 30517578200 |
| 16 | 152587890705 |
| 17 | 762939453210 |
| 18 | 3814697265715 |
| 19 | 19073486328220 |
| 20 | 95367431640725 |
| 21 | 476837158203230 |
| 22 | 2384185791015735 |
| 23 | 11920928955078240 |
| 24 | 59604644775390745 |
[1,10,35,140,645,3150,15655,78160,390665,1953170, 9765675,48828180,244140685,1220703190,6103515695, 30517578200,152587890705,762939453210, 3814697265715,19073486328220,95367431640725, 476837158203230,2384185791015735, 11920928955078240,59604644775390745] |