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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 6 |
| 7 | 21 |
| 8 | 68 |
| 9 | 186 |
| 10 | 495 |
| 11 | 1335 |
| 12 | 3744 |
| 13 | 10870 |
| 14 | 32120 |
| 15 | 95565 |
| 16 | 284830 |
| 17 | 850580 |
| 18 | 2548436 |
| 19 | 7669604 |
| 20 | 23192434 |
| 21 | 70443076 |
| 22 | 214768128 |
| 23 | 656857897 |
| 24 | 2014416494 |
| 25 | 6192794179 |
| 26 | 19081689920 |
| 27 | 58923909932 |
| 28 | 182331403224 |
| 29 | 565289067360 |
| 30 | 1755737915942 |
| 31 | 5462257817753 |
| 32 | 17019938788706 |
| 33 | 53109742992332 |
| 34 | 165952503650622 |
| 35 | 519222849063545 |
| 36 | 1626498619326355 |
| 37 | 5100995860701418 |
[1,1,1,1,1,6,21,68,186,495,1335,3744,10870,32120, 95565,284830,850580,2548436,7669604,23192434, 70443076,214768128,656857897,2014416494, 6192794179,19081689920,58923909932,182331403224, 565289067360,1755737915942,5462257817753, 17019938788706,53109742992332,165952503650622, 519222849063545,1626498619326355,5100995860701418] |