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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 21 |
| 3 | 132 |
| 4 | 429 |
| 5 | 1272 |
| 6 | 2826 |
| 7 | 5640 |
| 8 | 10461 |
| 9 | 17094 |
| 10 | 26847 |
| 11 | 41046 |
| 12 | 61041 |
| 13 | 84051 |
| 14 | 118974 |
| 15 | 157209 |
| 16 | 204393 |
| 17 | 264855 |
| 18 | 346524 |
| 19 | 428880 |
| 20 | 541683 |
| 21 | 654087 |
| 22 | 793611 |
| 23 | 961179 |
| 24 | 1167468 |
| 25 | 1357515 |
| 26 | 1615209 |
| 27 | 1891980 |
| 28 | 2198019 |
| 29 | 2530275 |
| 30 | 2957808 |
| 31 | 3341439 |
| 32 | 3860652 |
| 33 | 4371006 |
| 34 | 4959636 |
| 35 | 5572167 |
| 36 | 6277722 |
| 37 | 6950064 |
| 38 | 7859406 |
| 39 | 8763780 |
| 40 | 9722571 |
| 41 | 10687506 |
| 42 | 11934912 |
| 43 | 13029834 |
| 44 | 14450598 |
| 45 | 15805026 |
| 46 | 17250795 |
| 47 | 18863397 |
| 48 | 20763204 |
| 49 | 22372839 |
| 50 | 24450474 |
[3,21,132,429,1272,2826,5640,10461,17094,26847, 41046,61041,84051,118974,157209,204393,264855, 346524,428880,541683,654087,793611,961179,1167468, 1357515,1615209,1891980,2198019,2530275,2957808, 3341439,3860652,4371006,4959636,5572167,6277722, 6950064,7859406,8763780,9722571,10687506,11934912, 13029834,14450598,15805026,17250795,18863397, 20763204,22372839,24450474] |