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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 13 |
| 3 | 54 |
| 4 | 190 |
| 5 | 587 |
| 6 | 1659 |
| 7 | 4412 |
| 8 | 11244 |
| 9 | 27785 |
| 10 | 67089 |
| 11 | 159106 |
| 12 | 371930 |
| 13 | 859159 |
| 14 | 1964855 |
| 15 | 4454968 |
| 16 | 10025240 |
| 17 | 22411221 |
| 18 | 49804909 |
| 19 | 110097630 |
| 20 | 242217766 |
| 21 | 530575683 |
| 22 | 1157623603 |
| 23 | 2516577524 |
| 24 | 5452589700 |
| 25 | 11777599457 |
[1,3,13,54,190,587,1659,4412,11244,27785,67089, 159106,371930,859159,1964855,4454968,10025240, 22411221,49804909,110097630,242217766,530575683, 1157623603,2516577524,5452589700,11777599457] |