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| n | a(n) |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 5 |
| 3 | 15 |
| 4 | 43 |
| 5 | 103 |
| 6 | 263 |
| 7 | 591 |
| 8 | 1391 |
| 9 | 3103 |
| 10 | 7007 |
| 11 | 15039 |
| 12 | 33983 |
| 13 | 72063 |
| 14 | 156543 |
| 15 | 334591 |
| 16 | 722687 |
| 17 | 1510911 |
| 18 | 3255807 |
| 19 | 6773759 |
| 20 | 14433279 |
| 21 | 30193663 |
| 22 | 63535103 |
| 23 | 131264511 |
| 24 | 278589439 |
| 25 | 575004671 |
| 26 | 1200349183 |
| 27 | 2484846591 |
| 28 | 5189910527 |
| 29 | 10648256511 |
| 30 | 22287450111 |
| 31 | 45648642047 |
[0,1,5,15,43,103,263,591,1391,3103,7007,15039, 33983,72063,156543,334591,722687,1510911,3255807, 6773759,14433279,30193663,63535103,131264511, 278589439,575004671,1200349183,2484846591, 5189910527,10648256511,22287450111,45648642047] |