| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 6 |
| 3 | 10 |
| 4 | 62 |
| 5 | 176 |
| 6 | 734 |
| 7 | 3034 |
| 8 | 12962 |
| 9 | 55806 |
| 10 | 241462 |
| 11 | 1047244 |
| 12 | 4548392 |
| 13 | 19770622 |
| 14 | 85983476 |
| 15 | 374071534 |
| 16 | 1627718734 |
| 17 | 7083554700 |
| 18 | 30828250368 |
| 19 | 134171670508 |
| 20 | 583957263660 |
| 21 | 2541594468334 |
| 22 | 11062020222648 |
| 23 | 48146469919922 |
[0,6,10,62,176,734,3034,12962,55806,241462, 1047244,4548392,19770622,85983476,374071534, 1627718734,7083554700,30828250368,134171670508, 583957263660,2541594468334,11062020222648, 48146469919922] |