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| n | a(n) |
|---|---|
| 1 | 240 |
| 2 | 9439 |
| 3 | 127566 |
| 4 | 938895 |
| 5 | 4868362 |
| 6 | 19285211 |
| 7 | 64105154 |
| 8 | 183394583 |
| 9 | 471403286 |
| 10 | 1102425601 |
| 11 | 2401296076 |
| 12 | 4893740761 |
| 13 | 9479843984 |
| 14 | 17499293961 |
| 15 | 31078021378 |
| 16 | 53193428735 |
| 17 | 88367832130 |
| 18 | 142559457359 |
[240,9439,127566,938895,4868362,19285211,64105154, 183394583,471403286,1102425601,2401296076, 4893740761,9479843984,17499293961,31078021378, 53193428735,88367832130,142559457359] |