The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 13 |
| 3 | 125 |
| 4 | 932 |
| 5 | 5161 |
| 6 | 22362 |
| 7 | 80018 |
| 8 | 246115 |
| 9 | 669892 |
| 10 | 1649171 |
| 11 | 3734347 |
| 12 | 7880798 |
| 13 | 15663155 |
| 14 | 29566552 |
| 15 | 53371656 |
| 16 | 92651957 |
| 17 | 155403478 |
| 18 | 252828745 |
| 19 | 400298537 |
| 20 | 618516616 |
| 21 | 934914317 |
| 22 | 1385303558 |
| 23 | 2015818510 |
| 24 | 2885177847 |
| 25 | 4067301176 |
| 26 | 5654314927 |
| 27 | 7759984663 |
| 28 | 10523612450 |
| 29 | 14114439607 |
| 30 | 18736596836 |
[1,2,13,125,932,5161,22362,80018,246115,669892, 1649171,3734347,7880798,15663155,29566552, 53371656,92651957,155403478,252828745,400298537, 618516616,934914317,1385303558,2015818510, 2885177847,4067301176,5654314927,7759984663, 10523612450,14114439607,18736596836] |