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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 4 |
| 3 | 10 |
| 4 | 30 |
| 5 | 65 |
| 6 | 173 |
| 7 | 343 |
| 8 | 778 |
| 9 | 1518 |
| 10 | 3088 |
| 11 | 5609 |
| 12 | 10959 |
| 13 | 18990 |
| 14 | 34441 |
| 15 | 58903 |
| 16 | 102044 |
| 17 | 167499 |
| 18 | 282519 |
| 19 | 451529 |
| 20 | 737208 |
| 21 | 1160102 |
| 22 | 1836910 |
| 23 | 2828466 |
| 24 | 4410990 |
| 25 | 6670202 |
| 26 | 10161240 |
| 27 | 15186315 |
| 28 | 22758131 |
| 29 | 33480869 |
[1,4,10,30,65,173,343,778,1518,3088,5609,10959, 18990,34441,58903,102044,167499,282519,451529, 737208,1160102,1836910,2828466,4410990,6670202, 10161240,15186315,22758131,33480869] |