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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 3 |
| 4 | 18 |
| 5 | 57 |
| 6 | 137 |
| 7 | 280 |
| 8 | 517 |
| 9 | 863 |
| 10 | 1368 |
| 11 | 2069 |
| 12 | 3007 |
| 13 | 4218 |
| 14 | 5774 |
| 15 | 7704 |
| 16 | 10109 |
| 17 | 13025 |
| 18 | 16523 |
| 19 | 20671 |
| 20 | 25567 |
| 21 | 31274 |
| 22 | 37891 |
| 23 | 45529 |
| 24 | 54213 |
| 25 | 64082 |
| 26 | 75320 |
| 27 | 87901 |
| 28 | 102014 |
| 29 | 117736 |
| 30 | 135217 |
| 31 | 154606 |
| 32 | 176024 |
| 33 | 199502 |
| 34 | 225290 |
| 35 | 253485 |
| 36 | 284305 |
| 37 | 317811 |
| 38 | 354282 |
| 39 | 393618 |
| 40 | 436202 |
| 41 | 482332 |
[0,0,3,18,57,137,280,517,863,1368,2069,3007,4218, 5774,7704,10109,13025,16523,20671,25567,31274, 37891,45529,54213,64082,75320,87901,102014,117736, 135217,154606,176024,199502,225290,253485,284305, 317811,354282,393618,436202,482332] |