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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 0 |
| 5 | 1 |
| 6 | 5 |
| 7 | 17 |
| 8 | 54 |
| 9 | 163 |
| 10 | 465 |
| 11 | 1283 |
| 12 | 3480 |
| 13 | 9256 |
| 14 | 24282 |
| 15 | 62812 |
| 16 | 160106 |
| 17 | 401824 |
| 18 | 992033 |
| 19 | 2406329 |
| 20 | 5730955 |
| 21 | 13393760 |
| 22 | 30709772 |
| 23 | 69079030 |
| 24 | 152473837 |
| 25 | 330344629 |
| 26 | 702839150 |
| 27 | 1469214076 |
| 28 | 3019246455 |
| 29 | 6103105779 |
| 30 | 12142291541 |
| 31 | 23790590387 |
| 32 | 45932253637 |
| 33 | 87434850942 |
| 34 | 164188881007 |
[0,0,0,0,1,5,17,54,163,465,1283,3480,9256,24282, 62812,160106,401824,992033,2406329,5730955, 13393760,30709772,69079030,152473837,330344629, 702839150,1469214076,3019246455,6103105779, 12142291541,23790590387,45932253637,87434850942, 164188881007] |