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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 12 |
| 3 | 100 |
| 4 | 392 |
| 5 | 1554 |
| 6 | 3486 |
| 7 | 9690 |
| 8 | 18942 |
| 9 | 38610 |
| 10 | 65268 |
| 11 | 125116 |
| 12 | 186870 |
| 13 | 324646 |
| 14 | 472546 |
| 15 | 713354 |
| 16 | 1003888 |
| 17 | 1531908 |
| 18 | 2000638 |
| 19 | 2920970 |
| 20 | 3780950 |
[1,12,100,392,1554,3486,9690,18942,38610,65268, 125116,186870,324646,472546,713354,1003888, 1531908,2000638,2920970,3780950] |