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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 7 |
| 4 | 20 |
| 5 | 54 |
| 6 | 168 |
| 7 | 518 |
| 8 | 1702 |
| 9 | 5672 |
| 10 | 19413 |
| 11 | 67329 |
| 12 | 236994 |
| 13 | 842362 |
| 14 | 3022320 |
| 15 | 10924142 |
| 16 | 39749219 |
| 17 | 145457241 |
| 18 | 534996370 |
| 19 | 1976582432 |
| 20 | 7332199623 |
| 21 | 27298096431 |
| 22 | 101968071485 |
| 23 | 382033462335 |
| 24 | 1435270419582 |
| 25 | 5405847465772 |
| 26 | 20408264704999 |
| 27 | 77211968620103 |
| 28 | 292706146651697 |
| 29 | 1111698968597495 |
| 30 | 4229571286335997 |
| 31 | 16117966287887641 |
| 32 | 61515492682026560 |
| 33 | 235114188287816030 |
| 34 | 899821838980825557 |
| 35 | 3448133313264656915 |
[1,1,3,7,20,54,168,518,1702,5672,19413,67329, 236994,842362,3022320,10924142,39749219,145457241, 534996370,1976582432,7332199623,27298096431, 101968071485,382033462335,1435270419582, 5405847465772,20408264704999,77211968620103, 292706146651697,1111698968597495,4229571286335997, 16117966287887641,61515492682026560, 235114188287816030,899821838980825557, 3448133313264656915] |