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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 14 |
| 5 | 46 |
| 6 | 167 |
| 7 | 659 |
| 8 | 2836 |
| 9 | 13064 |
| 10 | 64076 |
| 11 | 333928 |
| 12 | 1834438 |
| 13 | 10592518 |
| 14 | 64136528 |
| 15 | 405519766 |
| 16 | 2672202304 |
| 17 | 18315499424 |
| 18 | 130245129112 |
| 19 | 959527765480 |
| 20 | 7311915167696 |
| 21 | 57536223460640 |
| 22 | 466963917417152 |
| 23 | 3904133599120624 |
| 24 | 33583586584746728 |
| 25 | 296948602314737576 |
[1,1,2,5,14,46,167,659,2836,13064,64076,333928, 1834438,10592518,64136528,405519766,2672202304, 18315499424,130245129112,959527765480, 7311915167696,57536223460640,466963917417152, 3904133599120624,33583586584746728, 296948602314737576] |