The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 1 |
| 4 | 10 |
| 5 | 13 |
| 6 | 138 |
| 7 | 101 |
| 8 | 1228 |
| 9 | 1923 |
| 10 | 8930 |
| 11 | 7303 |
| 12 | 115356 |
| 13 | 97249 |
| 14 | 1721846 |
| 15 | 1484475 |
| 16 | 388760 |
| 17 | 681971 |
| 18 | 14725926 |
| 19 | 13093585 |
| 20 | 308430212 |
| 21 | 1386466053 |
| 22 | 1685280806 |
| 23 | 1529091919 |
| 24 | 42052434936 |
| 25 | 38450390845 |
| 26 | 226713176794 |
| 27 | 208661769963 |
[0,1,1,10,13,138,101,1228,1923,8930,7303,115356, 97249,1721846,1484475,388760,681971,14725926, 13093585,308430212,1386466053,1685280806, 1529091919,42052434936,38450390845,226713176794, 208661769963] |