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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 11 |
| 3 | 18 |
| 4 | 75 |
| 5 | 172 |
| 6 | 372 |
| 7 | 482 |
| 8 | 732 |
| 9 | 3276 |
| 10 | 7965 |
| 11 | 13068 |
| 12 | 46476 |
| 13 | 103488 |
| 14 | 252240 |
| 15 | 727956 |
| 16 | 1795605 |
| 17 | 6030528 |
| 18 | 8769600 |
| 19 | 15436092 |
| 20 | 56747712 |
| 21 | 224518995 |
| 22 | 297780084 |
| 23 | 317961000 |
| 24 | 855489144 |
| 25 | 2691137721 |
| 26 | 58016937600 |
| 27 | 127198874880 |
| 28 | 228517311456 |
| 29 | 411814778112 |
[1,11,18,75,172,372,482,732,3276,7965,13068,46476, 103488,252240,727956,1795605,6030528,8769600, 15436092,56747712,224518995,297780084,317961000, 855489144,2691137721,58016937600,127198874880, 228517311456,411814778112] |