The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 2 | 3 |
| 3 | 9 |
| 4 | 33 |
| 5 | 152 |
| 6 | 867 |
| 7 | 5884 |
| 8 | 46085 |
| 9 | 408246 |
| 10 | 4032007 |
| 11 | 43908488 |
| 12 | 522547209 |
| 13 | 6745939210 |
| 14 | 93884313611 |
| 15 | 1401079680012 |
| 16 | 22317642547213 |
| 17 | 377917892352014 |
| 18 | 6778983923712015 |
| 19 | 128403161542656016 |
| 20 | 2560949482291200017 |
| 21 | 53645489280294912018 |
| 22 | 1177524571957493760019 |
| 23 | 27027108408834293760020 |
[3,9,33,152,867,5884,46085,408246,4032007, 43908488,522547209,6745939210,93884313611, 1401079680012,22317642547213,377917892352014, 6778983923712015,128403161542656016, 2560949482291200017,53645489280294912018, 1177524571957493760019,27027108408834293760020] |