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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 20 |
| 3 | 195 |
| 4 | 866 |
| 5 | 6021 |
| 6 | 12100 |
| 7 | 36861 |
| 8 | 58326 |
| 9 | 127770 |
| 10 | 329291 |
| 11 | 431996 |
| 12 | 886471 |
| 13 | 1343986 |
| 14 | 1629950 |
| 15 | 2336046 |
| 16 | 3796415 |
| 17 | 5853336 |
| 18 | 6695996 |
| 19 | 9774836 |
| 20 | 12347981 |
| 21 | 13810155 |
| 22 | 18982046 |
| 23 | 23157420 |
| 24 | 30666201 |
| 25 | 43352041 |
| 26 | 50999976 |
| 27 | 55182770 |
| 28 | 64314816 |
| 29 | 69284171 |
| 30 | 80080845 |
| 31 | 128024036 |
[2,20,195,866,6021,12100,36861,58326,127770, 329291,431996,886471,1343986,1629950,2336046, 3796415,5853336,6695996,9774836,12347981,13810155, 18982046,23157420,30666201,43352041,50999976, 55182770,64314816,69284171,80080845,128024036] |