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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 10 |
| 4 | 40 |
| 5 | 176 |
| 6 | 830 |
| 7 | 4115 |
| 8 | 21198 |
| 9 | 112559 |
| 10 | 612632 |
| 11 | 3404041 |
| 12 | 19251182 |
| 13 | 110558737 |
| 14 | 643625347 |
| 15 | 3792942385 |
| 16 | 22602071988 |
| 17 | 136073693419 |
| 18 | 827100093078 |
| 19 | 5073042015385 |
| 20 | 31385390615698 |
| 21 | 195795705705357 |
| 22 | 1231410381962373 |
| 23 | 7806727084866309 |
| 24 | 49885661271015892 |
| 25 | 321311108707030967 |
| 26 | 2086162636742801262 |
| 27 | 13655153319525415679 |
| 28 | 90125387322138673911 |
[1,1,3,10,40,176,830,4115,21198,112559,612632, 3404041,19251182,110558737,643625347,3792942385, 22602071988,136073693419,827100093078, 5073042015385,31385390615698,195795705705357, 1231410381962373,7806727084866309, 49885661271015892,321311108707030967, 2086162636742801262,13655153319525415679, 90125387322138673911] |