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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 2 |
| 4 | 2 |
| 5 | 2 |
| 6 | 4 |
| 7 | 4 |
| 8 | 4 |
| 9 | 6 |
| 10 | 6 |
| 11 | 6 |
| 12 | 9 |
| 13 | 9 |
| 14 | 9 |
| 15 | 12 |
| 16 | 12 |
| 17 | 12 |
| 18 | 16 |
| 19 | 16 |
| 20 | 16 |
| 21 | 20 |
| 22 | 20 |
| 23 | 20 |
| 24 | 25 |
| 25 | 25 |
| 26 | 25 |
| 27 | 30 |
| 28 | 30 |
| 29 | 30 |
| 30 | 36 |
| 31 | 36 |
| 32 | 36 |
| 33 | 42 |
| 34 | 42 |
| 35 | 42 |
| 36 | 49 |
| 37 | 49 |
| 38 | 49 |
| 39 | 56 |
| 40 | 56 |
| 41 | 56 |
| 42 | 64 |
| 43 | 64 |
| 44 | 64 |
| 45 | 72 |
| 46 | 72 |
| 47 | 72 |
| 48 | 81 |
| 49 | 81 |
| 50 | 81 |
| 51 | 90 |
| 52 | 90 |
| 53 | 90 |
| 54 | 100 |
| 55 | 100 |
| 56 | 100 |
| 57 | 110 |
| 58 | 110 |
| 59 | 110 |
| 60 | 121 |
| 61 | 121 |
| 62 | 121 |
| 63 | 132 |
| 64 | 132 |
| 65 | 132 |
[1,1,1,2,2,2,4,4,4,6,6,6,9,9,9,12,12,12,16,16,16, 20,20,20,25,25,25,30,30,30,36,36,36,42,42,42,49, 49,49,56,56,56,64,64,64,72,72,72,81,81,81,90,90, 90,100,100,100,110,110,110,121,121,121,132,132, 132] |