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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 11 |
| 5 | 29 |
| 6 | 87 |
| 7 | 279 |
| 8 | 903 |
| 9 | 2990 |
| 10 | 10343 |
| 11 | 36438 |
| 12 | 129027 |
| 13 | 468060 |
| 14 | 1727245 |
| 15 | 6402949 |
| 16 | 24000526 |
| 17 | 91225611 |
| 18 | 348672208 |
| 19 | 1339913947 |
| 20 | 5198901440 |
| 21 | 20295939931 |
| 22 | 79512175548 |
| 23 | 313402415099 |
| 24 | 1242354896065 |
| 25 | 4940265001927 |
| 26 | 19721255437363 |
| 27 | 79093149899843 |
| 28 | 318190739681634 |
| 29 | 1283561330395760 |
| 30 | 5196080410244929 |
[1,1,2,4,11,29,87,279,903,2990,10343,36438,129027, 468060,1727245,6402949,24000526,91225611, 348672208,1339913947,5198901440,20295939931, 79512175548,313402415099,1242354896065, 4940265001927,19721255437363,79093149899843, 318190739681634,1283561330395760,5196080410244929] |