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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 22 |
| 3 | 25 |
| 4 | 118 |
| 5 | 414 |
| 6 | 2745 |
| 7 | 10623 |
| 8 | 63201 |
| 9 | 1039161 |
| 10 | 1693864 |
| 11 | 2285297 |
| 12 | 52962021 |
| 13 | 66998865 |
| 14 | 232974402 |
| 15 | 315796805 |
| 16 | 336125877 |
| 17 | 834972771 |
| 18 | 1233903294 |
| 19 | 1309750075 |
| 20 | 1617454215 |
| 21 | 2056836133 |
| 22 | 5455816485 |
| 23 | 8589896196 |
| 24 | 9030058217 |
| 25 | 10622144467 |
| 26 | 12324258770 |
| 27 | 33725308558 |
[1,22,25,118,414,2745,10623,63201,1039161,1693864, 2285297,52962021,66998865,232974402,315796805, 336125877,834972771,1233903294,1309750075, 1617454215,2056836133,5455816485,8589896196, 9030058217,10622144467,12324258770,33725308558] |