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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 7 |
| 3 | 25 |
| 4 | 107 |
| 5 | 446 |
| 6 | 2007 |
| 7 | 8826 |
| 8 | 40717 |
| 9 | 184748 |
| 10 | 867389 |
| 11 | 4016951 |
| 12 | 19078567 |
| 13 | 89576514 |
| 14 | 428852271 |
| 15 | 2033468091 |
| 16 | 9793501197 |
| 17 | 46784585272 |
| 18 | 226364034325 |
| 19 | 1087647799101 |
| 20 | 5281738819743 |
| 21 | 25495198204130 |
| 22 | 124172939105885 |
| 23 | 601634383555610 |
| 24 | 2937357566671603 |
| 25 | 14275931732980038 |
| 26 | 69841390604939023 |
[1,2,7,25,107,446,2007,8826,40717,184748,867389, 4016951,19078567,89576514,428852271,2033468091, 9793501197,46784585272,226364034325,1087647799101, 5281738819743,25495198204130,124172939105885, 601634383555610,2937357566671603, 14275931732980038,69841390604939023] |