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| n | a(n) |
|---|---|
| 1 | 7 |
| 2 | 49 |
| 3 | 252 |
| 4 | 1036 |
| 5 | 3703 |
| 6 | 12453 |
| 7 | 42386 |
| 8 | 151882 |
| 9 | 567835 |
| 10 | 2147149 |
| 11 | 8034340 |
| 12 | 29610140 |
| 13 | 108114007 |
| 14 | 394245755 |
| 15 | 1442791435 |
| 16 | 5301606775 |
| 17 | 19520651849 |
| 18 | 71865418075 |
| 19 | 264265863322 |
| 20 | 970764224658 |
| 21 | 3564641145009 |
| 22 | 13091320557593 |
| 23 | 48095042423647 |
[7,49,252,1036,3703,12453,42386,151882,567835, 2147149,8034340,29610140,108114007,394245755, 1442791435,5301606775,19520651849,71865418075, 264265863322,970764224658,3564641145009, 13091320557593,48095042423647] |