The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 18 |
| 1 | 19 |
| 2 | 56 |
| 3 | 75 |
| 4 | 281 |
| 5 | 637 |
| 6 | 1555 |
| 7 | 3747 |
| 8 | 12796 |
| 9 | 16543 |
| 10 | 45882 |
| 11 | 62425 |
| 12 | 2293182 |
| 13 | 2355607 |
| 14 | 7004396 |
| 15 | 9360003 |
| 16 | 35084405 |
| 17 | 79528813 |
| 18 | 194142031 |
| 19 | 467812875 |
| 20 | 1597580656 |
| 21 | 2065393531 |
| 22 | 5728367718 |
| 23 | 7793761249 |
| 24 | 286303772682 |
| 25 | 294097533931 |
| 26 | 874498840544 |
| 27 | 1168596374475 |
[18,19,56,75,281,637,1555,3747,12796,16543,45882, 62425,2293182,2355607,7004396,9360003,35084405, 79528813,194142031,467812875,1597580656, 2065393531,5728367718,7793761249,286303772682, 294097533931,874498840544,1168596374475] |