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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 2 |
| 5 | 2 |
| 6 | 3 |
| 7 | 3 |
| 8 | 3 |
| 9 | 5 |
| 10 | 5 |
| 11 | 5 |
| 12 | 7 |
| 13 | 7 |
| 14 | 7 |
| 15 | 9 |
| 16 | 9 |
| 17 | 9 |
| 18 | 12 |
| 19 | 12 |
| 20 | 12 |
| 21 | 15 |
| 22 | 15 |
| 23 | 15 |
| 24 | 18 |
| 25 | 18 |
| 26 | 18 |
| 27 | 23 |
| 28 | 23 |
| 29 | 23 |
| 30 | 28 |
| 31 | 28 |
| 32 | 28 |
| 33 | 33 |
| 34 | 33 |
| 35 | 33 |
| 36 | 40 |
| 37 | 40 |
| 38 | 40 |
| 39 | 47 |
| 40 | 47 |
| 41 | 47 |
| 42 | 54 |
| 43 | 54 |
| 44 | 54 |
| 45 | 63 |
| 46 | 63 |
| 47 | 63 |
| 48 | 72 |
| 49 | 72 |
| 50 | 72 |
| 51 | 81 |
| 52 | 81 |
| 53 | 81 |
| 54 | 93 |
| 55 | 93 |
| 56 | 93 |
| 57 | 105 |
| 58 | 105 |
[1,1,1,2,2,2,3,3,3,5,5,5,7,7,7,9,9,9,12,12,12,15, 15,15,18,18,18,23,23,23,28,28,28,33,33,33,40,40, 40,47,47,47,54,54,54,63,63,63,72,72,72,81,81,81, 93,93,93,105,105] |