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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 2 |
| 3 | 6 |
| 4 | 17 |
| 5 | 43 |
| 6 | 100 |
| 7 | 220 |
| 8 | 467 |
| 9 | 969 |
| 10 | 1982 |
| 11 | 4018 |
| 12 | 8101 |
| 13 | 16279 |
| 14 | 32648 |
| 15 | 65400 |
| 16 | 130919 |
| 17 | 261973 |
| 18 | 524098 |
| 19 | 1048366 |
| 20 | 2096921 |
| 21 | 4194051 |
| 22 | 8388332 |
| 23 | 16776916 |
| 24 | 33554107 |
| 25 | 67108513 |
| 26 | 134217350 |
| 27 | 268435050 |
| 28 | 536870477 |
| 29 | 1073741359 |
[0,1,2,6,17,43,100,220,467,969,1982,4018,8101, 16279,32648,65400,130919,261973,524098,1048366, 2096921,4194051,8388332,16776916,33554107, 67108513,134217350,268435050,536870477,1073741359] |