| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 4 |
| 3 | 6 |
| 4 | 14 |
| 5 | 26 |
| 6 | 54 |
| 7 | 104 |
| 8 | 210 |
| 9 | 412 |
| 10 | 832 |
| 11 | 1654 |
| 12 | 3330 |
| 13 | 6670 |
| 14 | 13452 |
| 15 | 27004 |
| 16 | 54414 |
| 17 | 109400 |
| 18 | 220264 |
| 19 | 442938 |
| 20 | 891256 |
| 21 | 1791894 |
| 22 | 3603128 |
| 23 | 7241452 |
| 24 | 14552628 |
| 25 | 29234478 |
| 26 | 58720290 |
| 27 | 117911510 |
| 28 | 236729446 |
| 29 | 475169660 |
| 30 | 953616548 |
| 31 | 1913446072 |
| 32 | 3838773120 |
| 33 | 7700145556 |
| 34 | 15443494464 |
| 35 | 30969376788 |
| 36 | 62096345834 |
| 37 | 124493833506 |
[0,4,6,14,26,54,104,210,412,832,1654,3330,6670, 13452,27004,54414,109400,220264,442938,891256, 1791894,3603128,7241452,14552628,29234478, 58720290,117911510,236729446,475169660,953616548, 1913446072,3838773120,7700145556,15443494464, 30969376788,62096345834,124493833506] |