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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 4 |
| 2 | 7 |
| 3 | 20 |
| 4 | 35 |
| 5 | 60 |
| 6 | 124 |
| 7 | 200 |
| 8 | 324 |
| 9 | 524 |
| 10 | 865 |
| 11 | 1320 |
| 12 | 2016 |
| 13 | 3036 |
| 14 | 4453 |
| 15 | 6684 |
| 16 | 9668 |
| 17 | 13856 |
| 18 | 19792 |
| 19 | 27876 |
| 20 | 38956 |
| 21 | 54640 |
| 22 | 75320 |
| 23 | 103268 |
| 24 | 141191 |
| 25 | 191320 |
| 26 | 257892 |
| 27 | 346164 |
| 28 | 463284 |
| 29 | 615292 |
| 30 | 814883 |
| 31 | 1074556 |
| 32 | 1409904 |
| 33 | 1844284 |
| 34 | 2402756 |
| 35 | 3118020 |
| 36 | 4038164 |
| 37 | 5207344 |
| 38 | 6694116 |
[1,4,7,20,35,60,124,200,324,524,865,1320,2016, 3036,4453,6684,9668,13856,19792,27876,38956,54640, 75320,103268,141191,191320,257892,346164,463284, 615292,814883,1074556,1409904,1844284,2402756, 3118020,4038164,5207344,6694116] |