| n | a(n) |
|---|---|
| 0 | 2 |
| 1 | 7 |
| 2 | 30 |
| 3 | 127 |
| 4 | 538 |
| 5 | 2279 |
| 6 | 9654 |
| 7 | 40895 |
| 8 | 173234 |
| 9 | 733831 |
| 10 | 3108558 |
| 11 | 13168063 |
| 12 | 55780810 |
| 13 | 236291303 |
| 14 | 1000946022 |
| 15 | 4240075391 |
| 16 | 17961247586 |
| 17 | 76085065735 |
| 18 | 322301510526 |
| 19 | 1365291107839 |
| 20 | 5783465941882 |
| 21 | 24499154875367 |
| 22 | 103780085443350 |
| 23 | 439619496648767 |
| 24 | 1862258072038418 |
[2,7,30,127,538,2279,9654,40895,173234,733831, 3108558,13168063,55780810,236291303,1000946022, 4240075391,17961247586,76085065735,322301510526, 1365291107839,5783465941882,24499154875367, 103780085443350,439619496648767,1862258072038418] |