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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 0 |
| 3 | 1 |
| 4 | 33 |
| 5 | 413 |
| 6 | 2859 |
| 7 | 13976 |
| 8 | 54199 |
| 9 | 177848 |
| 10 | 513905 |
| 11 | 1342933 |
| 12 | 3233784 |
| 13 | 7275049 |
| 14 | 15451358 |
| 15 | 31234528 |
| 16 | 60485192 |
| 17 | 112793064 |
| 18 | 203424686 |
| 19 | 356097793 |
| 20 | 606862907 |
| 21 | 1009447181 |
| 22 | 1642504781 |
| 23 | 2619324320 |
| 24 | 4100669333 |
| 25 | 6311574992 |
| 26 | 9563095895 |
[0,0,1,33,413,2859,13976,54199,177848,513905, 1342933,3233784,7275049,15451358,31234528, 60485192,112793064,203424686,356097793,606862907, 1009447181,1642504781,2619324320,4100669333, 6311574992,9563095895] |