The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 6 |
| 2 | 50 |
| 3 | 210 |
| 4 | 630 |
| 5 | 1540 |
| 6 | 3276 |
| 7 | 6300 |
| 8 | 11220 |
| 9 | 18810 |
| 10 | 30030 |
| 11 | 46046 |
| 12 | 68250 |
| 13 | 98280 |
| 14 | 138040 |
| 15 | 189720 |
| 16 | 255816 |
| 17 | 339150 |
| 18 | 442890 |
| 19 | 570570 |
| 20 | 726110 |
| 21 | 913836 |
| 22 | 1138500 |
| 23 | 1405300 |
| 24 | 1719900 |
| 25 | 2088450 |
| 26 | 2517606 |
| 27 | 3014550 |
| 28 | 3587010 |
| 29 | 4243280 |
| 30 | 4992240 |
| 31 | 5843376 |
| 32 | 6806800 |
| 33 | 7893270 |
| 34 | 9114210 |
[0,6,50,210,630,1540,3276,6300,11220,18810,30030, 46046,68250,98280,138040,189720,255816,339150, 442890,570570,726110,913836,1138500,1405300, 1719900,2088450,2517606,3014550,3587010,4243280, 4992240,5843376,6806800,7893270,9114210] |