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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 7 |
| 3 | 25 |
| 4 | 79 |
| 5 | 278 |
| 6 | 966 |
| 7 | 3362 |
| 8 | 11642 |
| 9 | 40375 |
| 10 | 140102 |
| 11 | 486191 |
| 12 | 1686966 |
| 13 | 5853300 |
| 14 | 20309556 |
| 15 | 70470311 |
| 16 | 244518242 |
| 17 | 848429087 |
| 18 | 2943877082 |
| 19 | 10214660764 |
| 20 | 35442822154 |
| 21 | 122979474647 |
| 22 | 426714063696 |
| 23 | 1480612045993 |
| 24 | 5137426278616 |
[1,7,25,79,278,966,3362,11642,40375,140102,486191, 1686966,5853300,20309556,70470311,244518242, 848429087,2943877082,10214660764,35442822154, 122979474647,426714063696,1480612045993, 5137426278616] |