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| n | a(n) |
|---|---|
| 2 | 1 |
| 3 | 1 |
| 4 | 2 |
| 5 | 4 |
| 6 | 14 |
| 7 | 49 |
| 8 | 216 |
| 9 | 984 |
| 10 | 4862 |
| 11 | 24739 |
| 12 | 130338 |
| 13 | 701584 |
| 14 | 3852744 |
| 15 | 21489836 |
| 16 | 121525520 |
| 17 | 695307888 |
| 18 | 4019381790 |
| 19 | 23446201495 |
| 20 | 137875564710 |
| 21 | 816646459860 |
| 22 | 4868578092510 |
| 23 | 29196022525905 |
| 24 | 176022392938080 |
| 25 | 1066433501134560 |
| 26 | 6490009570139784 |
| 27 | 39659537885087124 |
| 28 | 243278423033093336 |
| 29 | 1497584057249141728 |
| 30 | 9249144367260811824 |
[1,1,2,4,14,49,216,984,4862,24739,130338,701584, 3852744,21489836,121525520,695307888,4019381790, 23446201495,137875564710,816646459860, 4868578092510,29196022525905,176022392938080, 1066433501134560,6490009570139784, 39659537885087124,243278423033093336, 1497584057249141728,9249144367260811824] |