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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 19 |
| 4 | 87 |
| 5 | 363 |
| 6 | 1719 |
| 7 | 7625 |
| 8 | 36805 |
| 9 | 169109 |
| 10 | 824893 |
| 11 | 3874641 |
| 12 | 19020537 |
| 13 | 90656173 |
| 14 | 446915921 |
| 15 | 2151851691 |
| 16 | 10640076983 |
| 17 | 51609398595 |
| 18 | 255754672359 |
| 19 | 1247387187887 |
| 20 | 6191910245851 |
| 21 | 30327782549171 |
| 22 | 150739274838343 |
| 23 | 740770047940151 |
| 24 | 3685618022970599 |
| 25 | 18160005964345643 |
| 26 | 90426095901607687 |
[1,1,5,19,87,363,1719,7625,36805,169109,824893, 3874641,19020537,90656173,446915921,2151851691, 10640076983,51609398595,255754672359, 1247387187887,6191910245851,30327782549171, 150739274838343,740770047940151,3685618022970599, 18160005964345643,90426095901607687] |