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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 8 |
| 3 | 32 |
| 4 | 143 |
| 5 | 646 |
| 6 | 3013 |
| 7 | 14216 |
| 8 | 67939 |
| 9 | 327200 |
| 10 | 1585980 |
| 11 | 7725527 |
| 12 | 37777737 |
| 13 | 185320840 |
| 14 | 911426406 |
| 15 | 4492064943 |
| 16 | 22178844495 |
| 17 | 109668362611 |
| 18 | 542968554654 |
| 19 | 2691156370891 |
| 20 | 13350845387786 |
| 21 | 66287180191579 |
| 22 | 329348650810692 |
| 23 | 1637379870230403 |
| 24 | 8144751559357207 |
| 25 | 40533435385906476 |
| 26 | 201805270245783128 |
[1,2,8,32,143,646,3013,14216,67939,327200,1585980, 7725527,37777737,185320840,911426406,4492064943, 22178844495,109668362611,542968554654, 2691156370891,13350845387786,66287180191579, 329348650810692,1637379870230403,8144751559357207, 40533435385906476,201805270245783128] |