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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 6 |
| 6 | 31 |
| 7 | 106 |
| 8 | 281 |
| 9 | 631 |
| 10 | 1306 |
| 11 | 2806 |
| 12 | 6931 |
| 13 | 19306 |
| 14 | 55070 |
| 15 | 150816 |
| 16 | 391161 |
| 17 | 977501 |
| 18 | 2426071 |
| 19 | 6141865 |
| 20 | 16000186 |
| 21 | 42465571 |
| 22 | 112950916 |
| 23 | 297793651 |
| 24 | 776866355 |
| 25 | 2015237231 |
| 26 | 5233754306 |
| 27 | 13668689206 |
| 28 | 35908153534 |
| 29 | 94633042267 |
| 30 | 249398115466 |
| 31 | 656105299636 |
| 32 | 1723150461561 |
[1,1,1,1,1,6,31,106,281,631,1306,2806,6931,19306, 55070,150816,391161,977501,2426071,6141865, 16000186,42465571,112950916,297793651,776866355, 2015237231,5233754306,13668689206,35908153534, 94633042267,249398115466,656105299636, 1723150461561] |