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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 14 |
| 5 | 44 |
| 6 | 152 |
| 7 | 538 |
| 8 | 1995 |
| 9 | 7662 |
| 10 | 29940 |
| 11 | 120398 |
| 12 | 491459 |
| 13 | 2038747 |
| 14 | 8581283 |
| 15 | 36510595 |
| 16 | 157045874 |
| 17 | 681735158 |
| 18 | 2982964821 |
| 19 | 13151583858 |
| 20 | 58359139202 |
| 21 | 260520699938 |
| 22 | 1169379642893 |
| 23 | 5274592297251 |
| 24 | 23900749201570 |
| 25 | 108751720395298 |
| 26 | 496735253829031 |
| 27 | 2276991119469184 |
| 28 | 10471775432100043 |
[1,1,2,5,14,44,152,538,1995,7662,29940,120398, 491459,2038747,8581283,36510595,157045874, 681735158,2982964821,13151583858,58359139202, 260520699938,1169379642893,5274592297251, 23900749201570,108751720395298,496735253829031, 2276991119469184,10471775432100043] |