The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 3 |
| 1 | 18 |
| 2 | 146 |
| 3 | 1242 |
| 4 | 10658 |
| 5 | 91818 |
| 6 | 793586 |
| 7 | 6880122 |
| 8 | 59823938 |
| 9 | 521638218 |
| 10 | 4560526226 |
| 11 | 39970994202 |
| 12 | 351149013218 |
| 13 | 3091621642218 |
| 14 | 27274838966066 |
| 15 | 241075504183482 |
| 16 | 2134495165562498 |
| 17 | 18928981513351818 |
| 18 | 168109033806481106 |
[3,18,146,1242,10658,91818,793586,6880122, 59823938,521638218,4560526226,39970994202, 351149013218,3091621642218,27274838966066, 241075504183482,2134495165562498, 18928981513351818,168109033806481106] |