The OEIS is supported by the many generous donors to the OEIS Foundation.
| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 20 |
| 3 | 42 |
| 4 | 80 |
| 5 | 138 |
| 6 | 232 |
| 7 | 386 |
| 8 | 640 |
| 9 | 1062 |
| 10 | 1764 |
| 11 | 2934 |
| 12 | 4884 |
| 13 | 8134 |
| 14 | 13548 |
| 15 | 22562 |
| 16 | 37560 |
| 17 | 62498 |
| 18 | 103936 |
| 19 | 172746 |
| 20 | 286936 |
| 21 | 476318 |
| 22 | 790220 |
| 23 | 1310222 |
| 24 | 2171180 |
| 25 | 3595918 |
| 26 | 5952452 |
| 27 | 9848346 |
| 28 | 16286240 |
| 29 | 26920122 |
| 30 | 44477464 |
| 31 | 73454354 |
| 32 | 121259824 |
| 33 | 200099094 |
[2,20,42,80,138,232,386,640,1062,1764,2934,4884, 8134,13548,22562,37560,62498,103936,172746,286936, 476318,790220,1310222,2171180,3595918,5952452, 9848346,16286240,26920122,44477464,73454354, 121259824,200099094] |