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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 5 |
| 3 | 10 |
| 4 | 20 |
| 5 | 34 |
| 6 | 61 |
| 7 | 100 |
| 8 | 165 |
| 9 | 260 |
| 10 | 408 |
| 11 | 620 |
| 12 | 940 |
| 13 | 1390 |
| 14 | 2045 |
| 15 | 2960 |
| 16 | 4257 |
| 17 | 6040 |
| 18 | 8525 |
| 19 | 11900 |
| 20 | 16522 |
| 21 | 22738 |
| 22 | 31130 |
| 23 | 42300 |
| 24 | 57210 |
| 25 | 76872 |
| 26 | 102834 |
| 27 | 136800 |
| 28 | 181230 |
| 29 | 238900 |
| 30 | 313725 |
| 31 | 410160 |
| 32 | 534330 |
| 33 | 693330 |
| 34 | 896655 |
| 35 | 1155420 |
| 36 | 1484274 |
| 37 | 1900420 |
| 38 | 2426215 |
| 39 | 3088100 |
[1,2,5,10,20,34,61,100,165,260,408,620,940,1390, 2045,2960,4257,6040,8525,11900,16522,22738,31130, 42300,57210,76872,102834,136800,181230,238900, 313725,410160,534330,693330,896655,1155420, 1484274,1900420,2426215,3088100] |