The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 13 |
| 3 | 67 |
| 4 | 349 |
| 5 | 1875 |
| 6 | 10285 |
| 7 | 57123 |
| 8 | 320317 |
| 9 | 1809587 |
| 10 | 10283149 |
| 11 | 58714627 |
| 12 | 336579101 |
| 13 | 1935878419 |
| 14 | 11166265837 |
| 15 | 64566715363 |
| 16 | 374148669949 |
| 17 | 2172215118963 |
| 18 | 12632572359757 |
| 19 | 73575490895043 |
| 20 | 429102329027293 |
| 21 | 2505638311638739 |
| 22 | 14647279574704045 |
| 23 | 85710562407867555 |
[1,3,13,67,349,1875,10285,57123,320317,1809587, 10283149,58714627,336579101,1935878419, 11166265837,64566715363,374148669949, 2172215118963,12632572359757,73575490895043, 429102329027293,2505638311638739, 14647279574704045,85710562407867555] |