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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 2 |
| 3 | 4 |
| 4 | 10 |
| 5 | 20 |
| 6 | 36 |
| 7 | 64 |
| 8 | 110 |
| 9 | 180 |
| 10 | 288 |
| 11 | 452 |
| 12 | 696 |
| 13 | 1052 |
| 14 | 1568 |
| 15 | 2304 |
| 16 | 3346 |
| 17 | 4808 |
| 18 | 6838 |
| 19 | 9636 |
| 20 | 13464 |
| 21 | 18664 |
| 22 | 25684 |
| 23 | 35104 |
| 24 | 47672 |
| 25 | 64348 |
| 26 | 86368 |
| 27 | 115304 |
| 28 | 153152 |
| 29 | 202452 |
| 30 | 266404 |
| 31 | 349032 |
| 32 | 455406 |
| 33 | 591856 |
| 34 | 766284 |
| 35 | 988544 |
| 36 | 1270862 |
| 37 | 1628380 |
| 38 | 2079828 |
| 39 | 2648296 |
| 40 | 3362180 |
[0,2,4,10,20,36,64,110,180,288,452,696,1052,1568, 2304,3346,4808,6838,9636,13464,18664,25684,35104, 47672,64348,86368,115304,153152,202452,266404, 349032,455406,591856,766284,988544,1270862, 1628380,2079828,2648296,3362180] |