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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 12 |
| 5 | 25 |
| 6 | 87 |
| 7 | 189 |
| 8 | 788 |
| 9 | 1893 |
| 10 | 7569 |
| 11 | 18601 |
| 12 | 80506 |
| 13 | 207493 |
| 14 | 874156 |
| 15 | 2280579 |
| 16 | 10100264 |
| 17 | 27140517 |
| 18 | 117684741 |
| 19 | 318421209 |
| 20 | 1430927370 |
| 21 | 3951930221 |
| 22 | 17460909038 |
| 23 | 48431305459 |
| 24 | 219878196682 |
| 25 | 619212387825 |
| 26 | 2771909420147 |
| 27 | 7828026283149 |
| 28 | 35809758410988 |
| 29 | 102329069152021 |
| 30 | 462524102337463 |
| 31 | 1324171950218941 |
[1,1,2,3,12,25,87,189,788,1893,7569,18601,80506, 207493,874156,2280579,10100264,27140517,117684741, 318421209,1430927370,3951930221,17460909038, 48431305459,219878196682,619212387825, 2771909420147,7828026283149,35809758410988, 102329069152021,462524102337463,1324171950218941] |