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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 3 |
| 4 | 6 |
| 5 | 17 |
| 6 | 42 |
| 7 | 118 |
| 8 | 321 |
| 9 | 920 |
| 10 | 2626 |
| 11 | 7679 |
| 12 | 22554 |
| 13 | 67115 |
| 14 | 200883 |
| 15 | 606238 |
| 16 | 1839448 |
| 17 | 5613892 |
| 18 | 17211963 |
| 19 | 53006846 |
| 20 | 163866246 |
| 21 | 508389780 |
| 22 | 1582286912 |
| 23 | 4939146731 |
| 24 | 15459006948 |
| 25 | 48505063741 |
| 26 | 152539740067 |
| 27 | 480726546083 |
| 28 | 1517979996460 |
| 29 | 4802074019769 |
| 30 | 15217153748772 |
| 31 | 48298352064093 |
| 32 | 153526087484475 |
[1,1,1,3,6,17,42,118,321,920,2626,7679,22554, 67115,200883,606238,1839448,5613892,17211963, 53006846,163866246,508389780,1582286912, 4939146731,15459006948,48505063741,152539740067, 480726546083,1517979996460,4802074019769, 15217153748772,48298352064093,153526087484475] |