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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 2 |
| 6 | 3 |
| 7 | 4 |
| 8 | 7 |
| 9 | 12 |
| 10 | 20 |
| 11 | 35 |
| 12 | 62 |
| 13 | 112 |
| 14 | 199 |
| 15 | 361 |
| 16 | 657 |
| 17 | 1206 |
| 18 | 2221 |
| 19 | 4110 |
| 20 | 7636 |
| 21 | 14234 |
| 22 | 26618 |
| 23 | 49910 |
| 24 | 93846 |
| 25 | 176906 |
| 26 | 334184 |
| 27 | 632602 |
| 28 | 1199892 |
| 29 | 2280164 |
| 30 | 4340064 |
| 31 | 8273610 |
| 32 | 15796439 |
| 33 | 30202620 |
| 34 | 57820648 |
| 35 | 110826888 |
| 36 | 212681976 |
| 37 | 408610024 |
| 38 | 785833480 |
| 39 | 1512776590 |
| 40 | 2915017360 |
[1,1,1,1,1,2,3,4,7,12,20,35,62,112,199,361,657, 1206,2221,4110,7636,14234,26618,49910,93846, 176906,334184,632602,1199892,2280164,4340064, 8273610,15796439,30202620,57820648,110826888, 212681976,408610024,785833480,1512776590, 2915017360] |