The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 4 |
| 2 | 8 |
| 3 | 24 |
| 4 | 64 |
| 5 | 176 |
| 6 | 480 |
| 7 | 1312 |
| 8 | 3584 |
| 9 | 9792 |
| 10 | 26752 |
| 11 | 73088 |
| 12 | 199680 |
| 13 | 545536 |
| 14 | 1490432 |
| 15 | 4071936 |
| 16 | 11124736 |
| 17 | 30393344 |
| 18 | 83036160 |
| 19 | 226859008 |
| 20 | 619790336 |
| 21 | 1693298688 |
| 22 | 4626178048 |
| 23 | 12638953472 |
| 24 | 34530263040 |
[0,4,8,24,64,176,480,1312,3584,9792,26752,73088, 199680,545536,1490432,4071936,11124736,30393344, 83036160,226859008,619790336,1693298688, 4626178048,12638953472,34530263040] |