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| n | a(n) |
|---|---|
| 6 | 0 |
| 7 | 1320 |
| 8 | 13656 |
| 9 | 96090 |
| 10 | 569602 |
| 11 | 3111243 |
| 12 | 16447329 |
| 13 | 87358763 |
| 14 | 475067757 |
| 15 | 2607565996 |
| 16 | 14310288148 |
| 17 | 78087401424 |
| 18 | 422646322560 |
| 19 | 2269565277936 |
| 20 | 12114270563852 |
| 21 | 64454693890844 |
| 22 | 342374934748155 |
| 23 | 1817028234672099 |
| 24 | 9636622425425550 |
| 25 | 51069856507725138 |
| 26 | 270408018010461065 |
[0,1320,13656,96090,569602,3111243,16447329, 87358763,475067757,2607565996,14310288148, 78087401424,422646322560,2269565277936, 12114270563852,64454693890844,342374934748155, 1817028234672099,9636622425425550, 51069856507725138,270408018010461065] |