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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 0 |
| 2 | 2 |
| 3 | 2 |
| 4 | 10 |
| 5 | 10 |
| 6 | 10 |
| 7 | 74 |
| 8 | 202 |
| 9 | 202 |
| 10 | 714 |
| 11 | 714 |
| 12 | 714 |
| 13 | 714 |
| 14 | 8906 |
| 15 | 25290 |
| 16 | 58058 |
| 17 | 123594 |
| 18 | 254666 |
| 19 | 516810 |
| 20 | 516810 |
| 21 | 1565386 |
| 22 | 1565386 |
| 23 | 5759690 |
| 24 | 14148298 |
| 25 | 14148298 |
| 26 | 47702730 |
| 27 | 47702730 |
| 28 | 181920458 |
| 29 | 450355914 |
| 30 | 987226826 |
| 31 | 987226826 |
| 32 | 3134710474 |
| 33 | 7429677770 |
| 34 | 7429677770 |
[0,0,2,2,10,10,10,74,202,202,714,714,714,714,8906, 25290,58058,123594,254666,516810,516810,1565386, 1565386,5759690,14148298,14148298,47702730, 47702730,181920458,450355914,987226826,987226826, 3134710474,7429677770,7429677770] |