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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 8 |
| 3 | 30 |
| 4 | 130 |
| 5 | 564 |
| 6 | 2557 |
| 7 | 11683 |
| 8 | 54346 |
| 9 | 254545 |
| 10 | 1203147 |
| 11 | 5716624 |
| 12 | 27310772 |
| 13 | 130979508 |
| 14 | 630438224 |
| 15 | 3043186518 |
| 16 | 14727732882 |
| 17 | 71430873409 |
| 18 | 347119061240 |
| 19 | 1689676501553 |
| 20 | 8237284859214 |
| 21 | 40211183449288 |
| 22 | 196532448155539 |
| 23 | 961599134863745 |
| 24 | 4709587019390239 |
| 25 | 23086704003927488 |
| 26 | 113265637193121309 |
[1,2,8,30,130,564,2557,11683,54346,254545,1203147, 5716624,27310772,130979508,630438224,3043186518, 14727732882,71430873409,347119061240, 1689676501553,8237284859214,40211183449288, 196532448155539,961599134863745,4709587019390239, 23086704003927488,113265637193121309] |