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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 13 |
| 5 | 35 |
| 6 | 94 |
| 7 | 255 |
| 8 | 691 |
| 9 | 1876 |
| 10 | 5092 |
| 11 | 13829 |
| 12 | 37553 |
| 13 | 101992 |
| 14 | 276995 |
| 15 | 752307 |
| 16 | 2043218 |
| 17 | 5549310 |
| 18 | 15071694 |
| 19 | 40934215 |
| 20 | 111175866 |
| 21 | 301949926 |
| 22 | 820085698 |
| 23 | 2227325273 |
| 24 | 6049340413 |
| 25 | 16429805791 |
| 26 | 44622800991 |
| 27 | 121194031561 |
| 28 | 329158925122 |
| 29 | 893984605415 |
| 30 | 2428032213452 |
[1,2,5,13,35,94,255,691,1876,5092,13829,37553, 101992,276995,752307,2043218,5549310,15071694, 40934215,111175866,301949926,820085698,2227325273, 6049340413,16429805791,44622800991,121194031561, 329158925122,893984605415,2428032213452] |