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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 5 |
| 3 | 19 |
| 4 | 63 |
| 5 | 185 |
| 6 | 502 |
| 7 | 1270 |
| 8 | 3046 |
| 9 | 6968 |
| 10 | 15335 |
| 11 | 32593 |
| 12 | 67241 |
| 13 | 135030 |
| 14 | 264784 |
| 15 | 508063 |
| 16 | 955990 |
| 17 | 1766742 |
| 18 | 3211871 |
| 19 | 5750824 |
| 20 | 10153083 |
| 21 | 17691868 |
| 22 | 30454468 |
| 23 | 51827503 |
| 24 | 87259758 |
| 25 | 145439278 |
| 26 | 240113437 |
| 27 | 392863105 |
| 28 | 637330514 |
| 29 | 1025589482 |
[1,5,19,63,185,502,1270,3046,6968,15335,32593, 67241,135030,264784,508063,955990,1766742,3211871, 5750824,10153083,17691868,30454468,51827503, 87259758,145439278,240113437,392863105,637330514, 1025589482] |