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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 1 |
| 5 | 5 |
| 6 | 19 |
| 7 | 63 |
| 8 | 195 |
| 9 | 579 |
| 10 | 1676 |
| 11 | 4774 |
| 12 | 13463 |
| 13 | 37739 |
| 14 | 105442 |
| 15 | 294188 |
| 16 | 820699 |
| 17 | 2291243 |
| 18 | 6405310 |
| 19 | 17937140 |
| 20 | 50327731 |
| 21 | 141498983 |
| 22 | 398666071 |
| 23 | 1125566111 |
| 24 | 3184339189 |
| 25 | 9026625285 |
| 26 | 25636264044 |
| 27 | 72940663938 |
| 28 | 207889060481 |
| 29 | 593474349373 |
| 30 | 1696848600299 |
| 31 | 4858687934567 |
[0,0,0,0,1,5,19,63,195,579,1676,4774,13463,37739, 105442,294188,820699,2291243,6405310,17937140, 50327731,141498983,398666071,1125566111, 3184339189,9026625285,25636264044,72940663938, 207889060481,593474349373,1696848600299, 4858687934567] |