The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 2 |
| 4 | 5 |
| 5 | 12 |
| 6 | 21 |
| 7 | 50 |
| 8 | 119 |
| 9 | 208 |
| 10 | 495 |
| 11 | 1178 |
| 12 | 2059 |
| 13 | 4900 |
| 14 | 11661 |
| 15 | 20382 |
| 16 | 48505 |
| 17 | 115432 |
| 18 | 201761 |
| 19 | 480150 |
| 20 | 1142659 |
| 21 | 1997228 |
| 22 | 4752995 |
| 23 | 11311158 |
| 24 | 19770519 |
| 25 | 47049800 |
| 26 | 111968921 |
| 27 | 195707962 |
| 28 | 465745005 |
| 29 | 1108378052 |
| 30 | 1937309101 |
| 31 | 4610400250 |
[0,1,2,5,12,21,50,119,208,495,1178,2059,4900, 11661,20382,48505,115432,201761,480150,1142659, 1997228,4752995,11311158,19770519,47049800, 111968921,195707962,465745005,1108378052, 1937309101,4610400250] |