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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 4 |
| 2 | 12 |
| 3 | 28 |
| 4 | 60 |
| 5 | 120 |
| 6 | 228 |
| 7 | 416 |
| 8 | 732 |
| 9 | 1252 |
| 10 | 2088 |
| 11 | 3408 |
| 12 | 5460 |
| 13 | 8600 |
| 14 | 13344 |
| 15 | 20424 |
| 16 | 30876 |
| 17 | 46152 |
| 18 | 68268 |
| 19 | 100016 |
| 20 | 145224 |
| 21 | 209120 |
| 22 | 298800 |
| 23 | 423840 |
| 24 | 597108 |
| 25 | 835804 |
| 26 | 1162824 |
| 27 | 1608508 |
| 28 | 2212896 |
| 29 | 3028632 |
| 30 | 4124664 |
| 31 | 5590976 |
| 32 | 7544604 |
| 33 | 10137264 |
| 34 | 13565016 |
[1,4,12,28,60,120,228,416,732,1252,2088,3408,5460, 8600,13344,20424,30876,46152,68268,100016,145224, 209120,298800,423840,597108,835804,1162824, 1608508,2212896,3028632,4124664,5590976,7544604, 10137264,13565016] |