| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 9 |
| 4 | 19 |
| 5 | 46 |
| 6 | 100 |
| 7 | 218 |
| 8 | 460 |
| 9 | 965 |
| 10 | 1975 |
| 11 | 3993 |
| 12 | 7975 |
| 13 | 15712 |
| 14 | 30650 |
| 15 | 59150 |
| 16 | 113093 |
| 17 | 214300 |
| 18 | 402812 |
| 19 | 751165 |
| 20 | 1390714 |
| 21 | 2557004 |
| 22 | 4670770 |
| 23 | 8479232 |
| 24 | 15302657 |
| 25 | 27462424 |
| 26 | 49021252 |
| 27 | 87057783 |
| 28 | 153850769 |
| 29 | 270614429 |
| 30 | 473850031 |
| 31 | 826125184 |
| 32 | 1434286323 |
| 33 | 2480145226 |
[1,1,3,9,19,46,100,218,460,965,1975,3993,7975, 15712,30650,59150,113093,214300,402812,751165, 1390714,2557004,4670770,8479232,15302657,27462424, 49021252,87057783,153850769,270614429,473850031, 826125184,1434286323,2480145226] |