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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 10 |
| 5 | 22 |
| 6 | 65 |
| 7 | 166 |
| 8 | 562 |
| 9 | 1648 |
| 10 | 5199 |
| 11 | 16864 |
| 12 | 57266 |
| 13 | 191065 |
| 14 | 643174 |
| 15 | 2276667 |
| 16 | 8015333 |
| 17 | 28228639 |
| 18 | 101105139 |
| 19 | 370143123 |
| 20 | 1348702341 |
| 21 | 4928075168 |
| 22 | 18351289405 |
| 23 | 68700034715 |
| 24 | 256666572281 |
| 25 | 966636795221 |
| 26 | 3682287354587 |
| 27 | 14030329659617 |
| 28 | 53521499184005 |
| 29 | 206034637093149 |
| 30 | 796949050223031 |
| 31 | 3081474368398721 |
[1,1,2,3,10,22,65,166,562,1648,5199,16864,57266, 191065,643174,2276667,8015333,28228639,101105139, 370143123,1348702341,4928075168,18351289405, 68700034715,256666572281,966636795221, 3682287354587,14030329659617,53521499184005, 206034637093149,796949050223031,3081474368398721] |