| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | -1 |
| 2 | 2 |
| 3 | 1 |
| 4 | 3 |
| 5 | 2 |
| 6 | 7 |
| 7 | 13 |
| 8 | 30 |
| 9 | 57 |
| 10 | 115 |
| 11 | 226 |
| 12 | 455 |
| 13 | 909 |
| 14 | 1822 |
| 15 | 3641 |
| 16 | 7283 |
| 17 | 14562 |
| 18 | 29127 |
| 19 | 58253 |
| 20 | 116510 |
| 21 | 233017 |
| 22 | 466035 |
| 23 | 932066 |
| 24 | 1864135 |
| 25 | 3728269 |
| 26 | 7456542 |
| 27 | 14913081 |
| 28 | 29826163 |
| 29 | 59652322 |
| 30 | 119304647 |
| 31 | 238609293 |
| 32 | 477218590 |
| 33 | 954437177 |
| 34 | 1908874355 |
| 35 | 3817748706 |
[0,-1,2,1,3,2,7,13,30,57,115,226,455,909,1822, 3641,7283,14562,29127,58253,116510,233017,466035, 932066,1864135,3728269,7456542,14913081,29826163, 59652322,119304647,238609293,477218590,954437177, 1908874355,3817748706] |