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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 9 |
| 4 | 30 |
| 5 | 103 |
| 6 | 384 |
| 7 | 1448 |
| 8 | 5657 |
| 9 | 22484 |
| 10 | 91109 |
| 11 | 373965 |
| 12 | 1556099 |
| 13 | 6536793 |
| 14 | 27720857 |
| 15 | 118517912 |
| 16 | 510272098 |
| 17 | 2210542606 |
| 18 | 9632036562 |
| 19 | 42184306699 |
| 20 | 185588435364 |
| 21 | 819950687056 |
| 22 | 3636717337195 |
| 23 | 16186362286732 |
| 24 | 72275528903043 |
| 25 | 323701780511341 |
| 26 | 1453804685181711 |
| 27 | 6546093937183779 |
| 28 | 29546360820193525 |
[1,1,3,9,30,103,384,1448,5657,22484,91109,373965, 1556099,6536793,27720857,118517912,510272098, 2210542606,9632036562,42184306699,185588435364, 819950687056,3636717337195,16186362286732, 72275528903043,323701780511341,1453804685181711, 6546093937183779,29546360820193525] |