| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 0 |
| 2 | 0 |
| 3 | 0 |
| 4 | 2 |
| 5 | 2 |
| 6 | 2 |
| 7 | 2 |
| 8 | 8 |
| 9 | 14 |
| 10 | 20 |
| 11 | 26 |
| 12 | 52 |
| 13 | 98 |
| 14 | 164 |
| 15 | 250 |
| 16 | 426 |
| 17 | 762 |
| 18 | 1328 |
| 19 | 2194 |
| 20 | 3682 |
| 21 | 6366 |
| 22 | 11072 |
| 23 | 18878 |
| 24 | 32038 |
| 25 | 54906 |
| 26 | 94860 |
| 27 | 163226 |
| 28 | 279634 |
| 29 | 479806 |
| 30 | 826776 |
| 31 | 1425542 |
| 32 | 2454020 |
| 33 | 4223170 |
| 34 | 7279164 |
| 35 | 12560466 |
| 36 | 21671314 |
| 37 | 37381714 |
| 38 | 64512676 |
| 39 | 111414042 |
[1,0,0,0,2,2,2,2,8,14,20,26,52,98,164,250,426,762, 1328,2194,3682,6366,11072,18878,32038,54906,94860, 163226,279634,479806,826776,1425542,2454020, 4223170,7279164,12560466,21671314,37381714, 64512676,111414042] |