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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 7 |
| 3 | 16 |
| 4 | 64 |
| 5 | 133 |
| 6 | 465 |
| 7 | 1008 |
| 8 | 3023 |
| 9 | 6695 |
| 10 | 18206 |
| 11 | 40175 |
| 12 | 103229 |
| 13 | 225470 |
| 14 | 549873 |
| 15 | 1194620 |
| 16 | 2801742 |
| 17 | 6015042 |
| 18 | 13686306 |
| 19 | 29063919 |
| 20 | 64424496 |
| 21 | 135362432 |
| 22 | 293512852 |
| 23 | 610061141 |
| 24 | 1298516539 |
| 25 | 2670738781 |
| 26 | 5591712472 |
| 27 | 11388116508 |
| 28 | 23499720744 |
| 29 | 47403692965 |
| 30 | 96564236754 |
[1,1,7,16,64,133,465,1008,3023,6695,18206,40175, 103229,225470,549873,1194620,2801742,6015042, 13686306,29063919,64424496,135362432,293512852, 610061141,1298516539,2670738781,5591712472, 11388116508,23499720744,47403692965,96564236754] |