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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 7 |
| 4 | 16 |
| 5 | 49 |
| 6 | 158 |
| 7 | 480 |
| 8 | 1565 |
| 9 | 5372 |
| 10 | 18168 |
| 11 | 63018 |
| 12 | 223069 |
| 13 | 790675 |
| 14 | 2837099 |
| 15 | 10275237 |
| 16 | 37365238 |
| 17 | 136780746 |
| 18 | 503454552 |
| 19 | 1860283966 |
| 20 | 6903032032 |
| 21 | 25710869751 |
| 22 | 96062102703 |
| 23 | 360005362169 |
| 24 | 1352895525992 |
| 25 | 5096746479429 |
| 26 | 19245661967963 |
| 27 | 72829157526334 |
| 28 | 276144309118166 |
| 29 | 1048989168151209 |
| 30 | 3991676310364631 |
| 31 | 15213832997014866 |
| 32 | 58073559070913632 |
| 33 | 221990591912157497 |
| 34 | 849708949683300960 |
[1,1,2,7,16,49,158,480,1565,5372,18168,63018, 223069,790675,2837099,10275237,37365238,136780746, 503454552,1860283966,6903032032,25710869751, 96062102703,360005362169,1352895525992, 5096746479429,19245661967963,72829157526334, 276144309118166,1048989168151209,3991676310364631, 15213832997014866,58073559070913632, 221990591912157497,849708949683300960] |