The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 8 | 1 |
| 9 | 16 |
| 10 | 136 |
| 11 | 824 |
| 12 | 4004 |
| 13 | 16608 |
| 14 | 61076 |
| 15 | 204200 |
| 16 | 631714 |
| 17 | 1831752 |
| 18 | 5027312 |
| 19 | 13159104 |
| 20 | 33049090 |
| 21 | 80030808 |
| 22 | 187613348 |
| 23 | 427201176 |
| 24 | 947520103 |
| 25 | 2051989360 |
| 26 | 4347996772 |
| 27 | 9030416704 |
| 28 | 18412343832 |
| 29 | 36905322248 |
| 30 | 72807201940 |
| 31 | 141525042736 |
| 32 | 271321432489 |
| 33 | 513454659312 |
[1,16,136,824,4004,16608,61076,204200,631714, 1831752,5027312,13159104,33049090,80030808, 187613348,427201176,947520103,2051989360, 4347996772,9030416704,18412343832,36905322248, 72807201940,141525042736,271321432489, 513454659312] |