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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 14 |
| 5 | 40 |
| 6 | 127 |
| 7 | 418 |
| 8 | 1424 |
| 9 | 5031 |
| 10 | 18209 |
| 11 | 67366 |
| 12 | 254186 |
| 13 | 974761 |
| 14 | 3791854 |
| 15 | 14943935 |
| 16 | 59552233 |
| 17 | 239744109 |
| 18 | 974027603 |
| 19 | 3989625078 |
| 20 | 16464722934 |
| 21 | 68411771010 |
| 22 | 286027517137 |
| 23 | 1202755713725 |
| 24 | 5084367828630 |
| 25 | 21598046004481 |
| 26 | 92163416534879 |
| 27 | 394937069941730 |
| 28 | 1699022185812757 |
| 29 | 7336018013119783 |
[1,1,2,5,14,40,127,418,1424,5031,18209,67366, 254186,974761,3791854,14943935,59552233,239744109, 974027603,3989625078,16464722934,68411771010, 286027517137,1202755713725,5084367828630, 21598046004481,92163416534879,394937069941730, 1699022185812757,7336018013119783] |