The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 6 |
| 2 | 33 |
| 3 | 262 |
| 4 | 2145 |
| 5 | 16182 |
| 6 | 116353 |
| 7 | 821142 |
| 8 | 5760705 |
| 9 | 40347046 |
| 10 | 282465249 |
| 11 | 1977312102 |
| 12 | 13841266465 |
| 13 | 96888981846 |
| 14 | 678223034433 |
| 15 | 4747561459318 |
| 16 | 33232930504065 |
| 17 | 232630513903686 |
| 18 | 1628413597805473 |
| 19 | 11398895185242822 |
[1,6,33,262,2145,16182,116353,821142,5760705, 40347046,282465249,1977312102,13841266465, 96888981846,678223034433,4747561459318, 33232930504065,232630513903686,1628413597805473, 11398895185242822] |