| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 15 |
| 3 | 87 |
| 4 | 559 |
| 5 | 3807 |
| 6 | 26919 |
| 7 | 195399 |
| 8 | 1445967 |
| 9 | 10859967 |
| 10 | 82527687 |
| 11 | 633165255 |
| 12 | 4896345487 |
| 13 | 38117454303 |
| 14 | 298435452135 |
| 15 | 2348094847047 |
| 16 | 18554434810831 |
| 17 | 147171478237695 |
| 18 | 1171272947140359 |
| 19 | 9349653181797063 |
| 20 | 74834845484454927 |
| 21 | 600441007306747167 |
| 22 | 4828337830880795943 |
| 23 | 38904633251921442375 |
[1,3,15,87,559,3807,26919,195399,1445967,10859967, 82527687,633165255,4896345487,38117454303, 298435452135,2348094847047,18554434810831, 147171478237695,1171272947140359,9349653181797063, 74834845484454927,600441007306747167, 4828337830880795943,38904633251921442375] |