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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 2 |
| 4 | 3 |
| 5 | 4 |
| 6 | 6 |
| 7 | 18 |
| 8 | 36 |
| 9 | 186 |
| 10 | 438 |
| 11 | 2268 |
| 12 | 2709 |
| 13 | 11898 |
| 14 | 18076 |
| 15 | 151596 |
| 16 | 228222 |
| 17 | 563786 |
| 18 | 5359842 |
| 19 | 32285433 |
| 20 | 257161401 |
| 21 | 551366532 |
| 22 | 621319212 |
| 23 | 716064597 |
| 24 | 2459962002 |
| 25 | 5018349804 |
| 26 | 5067084204 |
| 27 | 7300948726 |
| 28 | 42360367356 |
| 29 | 139853034114 |
| 30 | 176616961826 |
| 31 | 469606524278 |
| 32 | 669367713609 |
| 33 | 1274936571666 |
| 34 | 1284108810066 |
| 35 | 5809320306961 |
| 36 | 8866678870082 |
| 37 | 11073162740322 |
| 38 | 14952142559323 |
| 39 | 325005646077513 |
[0,1,2,3,4,6,18,36,186,438,2268,2709,11898,18076, 151596,228222,563786,5359842,32285433,257161401, 551366532,621319212,716064597,2459962002, 5018349804,5067084204,7300948726,42360367356, 139853034114,176616961826,469606524278, 669367713609,1274936571666,1284108810066, 5809320306961,8866678870082,11073162740322, 14952142559323,325005646077513] |