| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 3 |
| 3 | 9 |
| 4 | 20 |
| 5 | 52 |
| 6 | 105 |
| 7 | 253 |
| 8 | 536 |
| 9 | 1142 |
| 10 | 2421 |
| 11 | 4999 |
| 12 | 10278 |
| 13 | 20686 |
| 14 | 41512 |
| 15 | 81984 |
| 16 | 161029 |
| 17 | 312681 |
| 18 | 603070 |
| 19 | 1153284 |
| 20 | 2189331 |
| 21 | 4129537 |
| 22 | 7733317 |
| 23 | 14399693 |
| 24 | 26644337 |
| 25 | 49034811 |
| 26 | 89741600 |
| 27 | 163411148 |
| 28 | 296074694 |
| 29 | 533909026 |
| 30 | 958416113 |
| 31 | 1712893825 |
| 32 | 3048468607 |
| 33 | 5403248469 |
| 34 | 9539609984 |
[1,1,3,9,20,52,105,253,536,1142,2421,4999,10278, 20686,41512,81984,161029,312681,603070,1153284, 2189331,4129537,7733317,14399693,26644337, 49034811,89741600,163411148,296074694,533909026, 958416113,1712893825,3048468607,5403248469, 9539609984] |