The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 1 | 13 |
| 2 | 21 |
| 3 | 197 |
| 4 | 1991 |
| 5 | 1022859 |
| 6 | 1346570 |
| 7 | 1351632 |
| 8 | 15919007 |
| 9 | 22440783 |
| 10 | 415638567 |
| 11 | 9345895862 |
[13,21,197,1991,1022859,1346570,1351632,15919007, 22440783,415638567,9345895862] |