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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 10 |
| 2 | 52 |
| 3 | 208 |
| 4 | 736 |
| 5 | 2440 |
| 6 | 7792 |
| 7 | 24328 |
| 8 | 74896 |
| 9 | 228520 |
| 10 | 693232 |
| 11 | 2095048 |
| 12 | 6315856 |
| 13 | 19009000 |
| 14 | 57149872 |
| 15 | 171695368 |
| 16 | 515577616 |
| 17 | 1547715880 |
| 18 | 4645113712 |
| 19 | 13939273288 |
| 20 | 41825684176 |
| 21 | 125492781160 |
| 22 | 376509800752 |
| 23 | 1129592316808 |
| 24 | 3388902779536 |
| 25 | 10166959996840 |
| 26 | 30501383306992 |
| 27 | 91505156553928 |
[1,10,52,208,736,2440,7792,24328,74896,228520, 693232,2095048,6315856,19009000,57149872, 171695368,515577616,1547715880,4645113712, 13939273288,41825684176,125492781160,376509800752, 1129592316808,3388902779536,10166959996840, 30501383306992,91505156553928] |