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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 21 |
| 6 | 31 |
| 7 | 113 |
| 8 | 169 |
| 9 | 8053 |
| 10 | 15871 |
| 11 | 71325 |
| 12 | 300147 |
| 13 | 816401 |
| 14 | 63105953 |
| 15 | 161203747 |
| 16 | 856049593 |
| 17 | 4050514725 |
| 18 | 25570388671 |
| 19 | 80377109117 |
| 20 | 12126315199099 |
| 21 | 36747628912981 |
| 22 | 233849676829957 |
| 23 | 1239662165799711 |
| 24 | 8321234529548651 |
| 25 | 59953576690379081 |
[1,0,1,1,1,21,31,113,169,8053,15871,71325,300147, 816401,63105953,161203747,856049593,4050514725, 25570388671,80377109117,12126315199099, 36747628912981,233849676829957,1239662165799711, 8321234529548651,59953576690379081] |