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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 4 |
| 4 | 8 |
| 5 | 16 |
| 6 | 35 |
| 7 | 77 |
| 8 | 179 |
| 9 | 440 |
| 10 | 1160 |
| 11 | 3264 |
| 12 | 9950 |
| 13 | 33206 |
| 14 | 121943 |
| 15 | 494011 |
| 16 | 2235399 |
| 17 | 11391306 |
| 18 | 65287199 |
| 19 | 422908306 |
| 20 | 3130775625 |
| 21 | 26490210964 |
| 22 | 255257056748 |
| 23 | 2825013955541 |
| 24 | 36147331371446 |
| 25 | 531237157370531 |
| 26 | 8965348473026888 |
[1,1,2,4,8,16,35,77,179,440,1160,3264,9950,33206, 121943,494011,2235399,11391306,65287199,422908306, 3130775625,26490210964,255257056748,2825013955541, 36147331371446,531237157370531,8965348473026888] |