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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 4 |
| 3 | 10 |
| 4 | 35 |
| 5 | 286 |
| 6 | 969 |
| 7 | 4495 |
| 8 | 12341 |
| 9 | 35990 |
| 10 | 62196 |
| 11 | 176851 |
| 12 | 209934 |
| 13 | 437989 |
| 14 | 562475 |
| 15 | 971970 |
| 16 | 1179616 |
| 17 | 1293699 |
| 18 | 1975354 |
| 19 | 2303960 |
| 20 | 3280455 |
| 21 | 3737581 |
| 22 | 5061836 |
| 23 | 7023974 |
| 24 | 12347930 |
| 25 | 13436856 |
| 26 | 16435111 |
| 27 | 23706021 |
| 28 | 30865405 |
| 29 | 35999900 |
| 30 | 39338069 |
[1,4,10,35,286,969,4495,12341,35990,62196,176851, 209934,437989,562475,971970,1179616,1293699, 1975354,2303960,3280455,3737581,5061836,7023974, 12347930,13436856,16435111,23706021,30865405, 35999900,39338069] |