The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 5 |
| 3 | 55 |
| 4 | 849 |
| 5 | 17701 |
| 6 | 464173 |
| 7 | 14717235 |
| 8 | 547743521 |
| 9 | 23418551881 |
| 10 | 1131271398261 |
| 11 | 60941609727439 |
| 12 | 3622478292965425 |
| 13 | 235533653451029805 |
| 14 | 16629469072027244189 |
| 15 | 1267012397537263762891 |
| 16 | 103618232946308849804097 |
| 17 | 9053648828215599307042705 |
| 18 | 841725575703516474238796389 |
[1,1,5,55,849,17701,464173,14717235,547743521, 23418551881,1131271398261,60941609727439, 3622478292965425,235533653451029805, 16629469072027244189,1267012397537263762891, 103618232946308849804097, 9053648828215599307042705, 841725575703516474238796389] |