The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 1 | 4 |
| 2 | 81 |
| 3 | 2116 |
| 4 | 58081 |
| 5 | 1612900 |
| 6 | 44903401 |
| 7 | 1250753956 |
| 8 | 34842328921 |
| 9 | 970622980804 |
| 10 | 27039303204489 |
| 11 | 753252725702500 |
| 12 | 20983889126032561 |
| 13 | 584562920742585316 |
| 14 | 16284579460194091201 |
| 15 | 453650957002812576484 |
| 16 | 12637673040690140943889 |
[4,81,2116,58081,1612900,44903401,1250753956, 34842328921,970622980804,27039303204489, 753252725702500,20983889126032561, 584562920742585316,16284579460194091201, 453650957002812576484,12637673040690140943889] |