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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 12 |
| 2 | 77 |
| 3 | 352 |
| 4 | 1286 |
| 5 | 3992 |
| 6 | 10933 |
| 7 | 27092 |
| 8 | 61841 |
| 9 | 131768 |
| 10 | 264759 |
| 11 | 505660 |
| 12 | 923858 |
| 13 | 1623116 |
| 14 | 2753972 |
| 15 | 4528964 |
| 16 | 7240871 |
| 17 | 11284064 |
| 18 | 17178942 |
| 19 | 25599288 |
| 20 | 37402222 |
| 21 | 53660256 |
| 22 | 75694775 |
| 23 | 105110084 |
| 24 | 143826980 |
| 25 | 194114636 |
| 26 | 258619428 |
| 27 | 340389204 |
[1,12,77,352,1286,3992,10933,27092,61841,131768, 264759,505660,923858,1623116,2753972,4528964, 7240871,11284064,17178942,25599288,37402222, 53660256,75694775,105110084,143826980,194114636, 258619428,340389204] |