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| n | a(n) |
|---|---|
| 1 | 0 |
| 2 | 1 |
| 3 | 2 |
| 4 | 5 |
| 5 | 9 |
| 6 | 18 |
| 7 | 34 |
| 8 | 66 |
| 9 | 127 |
| 10 | 249 |
| 11 | 490 |
| 12 | 972 |
| 13 | 1936 |
| 14 | 3874 |
| 15 | 7772 |
| 16 | 15623 |
| 17 | 31439 |
| 18 | 63308 |
| 19 | 127506 |
| 20 | 256782 |
| 21 | 516970 |
| 22 | 1040340 |
| 23 | 2092450 |
| 24 | 4206146 |
| 25 | 8449953 |
| 26 | 16965459 |
| 27 | 34042784 |
| 28 | 68272206 |
| 29 | 136847328 |
| 30 | 274168858 |
| 31 | 549042730 |
| 32 | 1099050180 |
| 33 | 2199222960 |
[0,1,2,5,9,18,34,66,127,249,490,972,1936,3874, 7772,15623,31439,63308,127506,256782,516970, 1040340,2092450,4206146,8449953,16965459,34042784, 68272206,136847328,274168858,549042730,1099050180, 2199222960] |