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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 4 |
| 3 | 18 |
| 4 | 50 |
| 5 | 136 |
| 6 | 262 |
| 7 | 583 |
| 8 | 974 |
| 9 | 1794 |
| 10 | 2603 |
| 11 | 4560 |
| 12 | 6190 |
| 13 | 9987 |
| 14 | 12617 |
| 15 | 19419 |
| 16 | 24264 |
| 17 | 35818 |
| 18 | 41262 |
| 19 | 61133 |
| 20 | 70126 |
| 21 | 97274 |
| 22 | 110076 |
| 23 | 154038 |
| 24 | 167176 |
| 25 | 230205 |
| 26 | 247554 |
| 27 | 328518 |
| 28 | 357811 |
| 29 | 476360 |
| 30 | 485118 |
| 31 | 660061 |
| 32 | 688320 |
| 33 | 874343 |
| 34 | 917049 |
| 35 | 1189870 |
| 36 | 1192404 |
[0,4,18,50,136,262,583,974,1794,2603,4560,6190, 9987,12617,19419,24264,35818,41262,61133,70126, 97274,110076,154038,167176,230205,247554,328518, 357811,476360,485118,660061,688320,874343,917049, 1189870,1192404] |