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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 6 |
| 2 | 13 |
| 3 | 45 |
| 4 | 328 |
| 5 | 373 |
| 6 | 1447 |
| 7 | 1820 |
| 8 | 5087 |
| 9 | 6907 |
| 10 | 25808 |
| 11 | 32715 |
| 12 | 254813 |
| 13 | 797154 |
| 14 | 1849121 |
| 15 | 11891880 |
| 16 | 382389281 |
| 17 | 2306227566 |
| 18 | 4994844413 |
| 19 | 17290760805 |
| 20 | 126030170048 |
| 21 | 143320930853 |
| 22 | 555992962607 |
| 23 | 699313893460 |
| 24 | 1954620749527 |
| 25 | 2653934642987 |
| 26 | 9916424678488 |
| 27 | 12570359321475 |
[1,6,13,45,328,373,1447,1820,5087,6907,25808, 32715,254813,797154,1849121,11891880,382389281, 2306227566,4994844413,17290760805,126030170048, 143320930853,555992962607,699313893460, 1954620749527,2653934642987,9916424678488, 12570359321475] |