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| n | a(n) |
|---|---|
| 3 | 0 |
| 4 | 2 |
| 5 | 2 |
| 6 | 6 |
| 7 | 13 |
| 8 | 29 |
| 9 | 53 |
| 10 | 131 |
| 11 | 284 |
| 12 | 698 |
| 13 | 1349 |
| 14 | 3278 |
| 15 | 6697 |
| 16 | 16939 |
| 17 | 38375 |
| 18 | 97676 |
| 19 | 236182 |
| 20 | 612904 |
| 21 | 1537369 |
| 22 | 4095502 |
| 23 | 10573599 |
| 24 | 28414576 |
| 25 | 74785048 |
| 26 | 200727205 |
| 27 | 531637446 |
| 28 | 1420536167 |
| 29 | 3759784818 |
| 30 | 9994893247 |
| 31 | 26403749078 |
[0,2,2,6,13,29,53,131,284,698,1349,3278,6697, 16939,38375,97676,236182,612904,1537369,4095502, 10573599,28414576,74785048,200727205,531637446, 1420536167,3759784818,9994893247,26403749078] |