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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 5 |
| 3 | 16 |
| 4 | 45 |
| 5 | 116 |
| 6 | 284 |
| 7 | 673 |
| 8 | 1557 |
| 9 | 3535 |
| 10 | 7910 |
| 11 | 17502 |
| 12 | 38376 |
| 13 | 83500 |
| 14 | 180479 |
| 15 | 387881 |
| 16 | 829605 |
| 17 | 1766998 |
| 18 | 3749765 |
| 19 | 7931114 |
| 20 | 16724870 |
| 21 | 35173777 |
| 22 | 73794660 |
| 23 | 154485527 |
| 24 | 322771344 |
| 25 | 673155141 |
| 26 | 1401536934 |
| 27 | 2913490375 |
| 28 | 6047714599 |
| 29 | 12536770558 |
| 30 | 25956242579 |
| 31 | 53678385266 |
[1,5,16,45,116,284,673,1557,3535,7910,17502,38376, 83500,180479,387881,829605,1766998,3749765, 7931114,16724870,35173777,73794660,154485527, 322771344,673155141,1401536934,2913490375, 6047714599,12536770558,25956242579,53678385266] |