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| n | a(n) |
|---|---|
| 1 | 3 |
| 2 | 11 |
| 3 | 24 |
| 4 | 89 |
| 5 | 191 |
| 6 | 748 |
| 7 | 1573 |
| 8 | 6259 |
| 9 | 13176 |
| 10 | 52497 |
| 11 | 110739 |
| 12 | 441340 |
| 13 | 931361 |
| 14 | 3713195 |
| 15 | 7836336 |
| 16 | 31247585 |
| 17 | 65947255 |
| 18 | 262980516 |
| 19 | 555025545 |
| 20 | 2213339483 |
| 21 | 4671332880 |
| 22 | 18628563209 |
| 23 | 39316357723 |
| 24 | 156788159916 |
| 25 | 330908274229 |
| 26 | 1319617809715 |
[3,11,24,89,191,748,1573,6259,13176,52497,110739, 441340,931361,3713195,7836336,31247585,65947255, 262980516,555025545,2213339483,4671332880, 18628563209,39316357723,156788159916,330908274229, 1319617809715] |