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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 9 |
| 5 | 9 |
| 6 | 9 |
| 7 | 18 |
| 8 | 18 |
| 9 | 18 |
| 10 | 18 |
| 11 | 27 |
| 12 | 27 |
| 13 | 27 |
| 14 | 27 |
| 15 | 27 |
| 16 | 36 |
| 17 | 36 |
| 18 | 45 |
| 19 | 45 |
| 20 | 45 |
| 21 | 45 |
| 22 | 54 |
| 23 | 54 |
| 24 | 54 |
| 25 | 63 |
| 26 | 63 |
| 27 | 72 |
| 28 | 72 |
| 29 | 72 |
| 30 | 72 |
| 31 | 81 |
| 32 | 81 |
| 33 | 81 |
| 34 | 81 |
| 35 | 99 |
| 36 | 108 |
| 37 | 108 |
| 38 | 108 |
| 39 | 108 |
| 40 | 117 |
| 41 | 117 |
| 42 | 117 |
| 43 | 117 |
| 44 | 126 |
| 45 | 126 |
| 46 | 135 |
| 47 | 135 |
| 48 | 135 |
| 49 | 135 |
| 50 | 135 |
| 51 | 144 |
| 52 | 144 |
| 53 | 144 |
| 54 | 153 |
| 55 | 153 |
| 56 | 153 |
| 57 | 162 |
| 58 | 162 |
| 59 | 171 |
| 60 | 171 |
[0,0,0,9,9,9,18,18,18,18,27,27,27,27,27,36,36,45, 45,45,45,54,54,54,63,63,72,72,72,72,81,81,81,81, 99,108,108,108,108,117,117,117,117,126,126,135, 135,135,135,135,144,144,144,153,153,153,162,162, 171,171] |