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A001431 as a simple table
| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 1 |
| 5 | 2 |
| 6 | 5 |
| 7 | 10 |
| 8 | 24 |
| 9 | 63 |
| 10 | 165 |
| 11 | 467 |
| 12 | 1405 |
| 13 | 4435 |
| 14 | 14775 |
| 15 | 51814 |
| 16 | 190443 |
| 17 | 732472 |
| 18 | 2939612 |
| 19 | 12277230 |
| 20 | 53233295 |
| 21 | 239083372 |
| 22 | 1109921554 |
| 23 | 5316143531 |
| 24 | 26225625392 |
| 25 | 133050795412 |
| 26 | 693227353094 |
| 27 | 3704785464812 |
| 28 | 20285853687809 |
| 29 | 113690627637475 |
| 30 | 651559904414667 |
[0,0,1,1,2,5,10,24,63,165,467,1405,4435,14775, 51814,190443,732472,2939612,12277230,53233295, 239083372,1109921554,5316143531,26225625392, 133050795412,693227353094,3704785464812, 20285853687809,113690627637475,651559904414667] |