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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 2 |
| 3 | 3 |
| 4 | 4 |
| 5 | 4 |
| 6 | 6 |
| 7 | 6 |
| 8 | 6 |
| 9 | 15 |
| 10 | 20 |
| 11 | 20 |
| 12 | 33 |
| 13 | 38 |
| 14 | 38 |
| 15 | 85 |
| 16 | 90 |
| 17 | 90 |
| 18 | 229 |
| 19 | 252 |
| 20 | 252 |
| 21 | 483 |
| 22 | 638 |
| 23 | 638 |
| 24 | 1395 |
| 25 | 1864 |
| 26 | 1864 |
| 27 | 3705 |
| 28 | 4830 |
| 29 | 4830 |
| 30 | 10395 |
| 31 | 13772 |
| 32 | 13772 |
| 33 | 31995 |
| 34 | 40950 |
| 35 | 40950 |
| 36 | 89595 |
| 37 | 97490 |
| 38 | 97490 |
| 39 | 272235 |
| 40 | 314490 |
| 41 | 314490 |
[1,2,2,3,4,4,6,6,6,15,20,20,33,38,38,85,90,90,229, 252,252,483,638,638,1395,1864,1864,3705,4830,4830, 10395,13772,13772,31995,40950,40950,89595,97490, 97490,272235,314490,314490] |