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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 12 |
| 2 | 78 |
| 3 | 376 |
| 4 | 1509 |
| 5 | 5316 |
| 6 | 16966 |
| 7 | 50088 |
| 8 | 138738 |
| 9 | 364284 |
| 10 | 913824 |
| 11 | 2203368 |
| 12 | 5130999 |
| 13 | 11585208 |
| 14 | 25444278 |
| 15 | 54504160 |
| 16 | 114133296 |
| 17 | 234091152 |
| 18 | 471062830 |
| 19 | 931388232 |
| 20 | 1811754522 |
| 21 | 3471186596 |
| 22 | 6556994502 |
| 23 | 12222818640 |
| 24 | 22502406793 |
| 25 | 40944396120 |
| 26 | 73680871326 |
| 27 | 131211105208 |
| 28 | 231355524048 |
| 29 | 404110659732 |
[1,12,78,376,1509,5316,16966,50088,138738,364284, 913824,2203368,5130999,11585208,25444278,54504160, 114133296,234091152,471062830,931388232, 1811754522,3471186596,6556994502,12222818640, 22502406793,40944396120,73680871326,131211105208, 231355524048,404110659732] |