| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 4 |
| 3 | 9 |
| 4 | 44 |
| 5 | 127 |
| 6 | 619 |
| 7 | 1989 |
| 8 | 9856 |
| 9 | 33919 |
| 10 | 168677 |
| 11 | 607001 |
| 12 | 3024616 |
| 13 | 11240063 |
| 14 | 56097646 |
| 15 | 213651441 |
| 16 | 1066929850 |
| 17 | 4142201763 |
| 18 | 20695048729 |
| 19 | 81607888787 |
| 20 | 407840022294 |
| 21 | 1629154166409 |
| 22 | 8143064177452 |
| 23 | 32884145423379 |
| 24 | 164385396321806 |
| 25 | 670058403611511 |
| 26 | 3349805478222521 |
| 27 | 13765134471463579 |
[1,1,4,9,44,127,619,1989,9856,33919,168677,607001, 3024616,11240063,56097646,213651441,1066929850, 4142201763,20695048729,81607888787,407840022294, 1629154166409,8143064177452,32884145423379, 164385396321806,670058403611511,3349805478222521, 13765134471463579] |