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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 20 |
| 3 | 161 |
| 4 | 237 |
| 5 | 341 |
| 6 | 1140 |
| 7 | 1580 |
| 8 | 2184 |
| 9 | 6837 |
| 10 | 9401 |
| 11 | 12921 |
| 12 | 40040 |
| 13 | 54984 |
| 14 | 75500 |
| 15 | 233561 |
| 16 | 320661 |
| 17 | 440237 |
| 18 | 1361484 |
| 19 | 1869140 |
| 20 | 2566080 |
| 21 | 7935501 |
| 22 | 10894337 |
| 23 | 14956401 |
| 24 | 46251680 |
| 25 | 63497040 |
| 26 | 87172484 |
| 27 | 269574737 |
| 28 | 370088061 |
| 29 | 508078661 |
| 30 | 1571196900 |
| 31 | 2157031484 |
| 32 | 2961299640 |
[0,20,161,237,341,1140,1580,2184,6837,9401,12921, 40040,54984,75500,233561,320661,440237,1361484, 1869140,2566080,7935501,10894337,14956401, 46251680,63497040,87172484,269574737,370088061, 508078661,1571196900,2157031484,2961299640] |