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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 5 |
| 3 | 25 |
| 4 | 101 |
| 5 | 385 |
| 6 | 1397 |
| 7 | 4921 |
| 8 | 16949 |
| 9 | 57409 |
| 10 | 191909 |
| 11 | 634777 |
| 12 | 2081477 |
| 13 | 6775873 |
| 14 | 21921941 |
| 15 | 70548793 |
| 16 | 225995285 |
| 17 | 721032577 |
| 18 | 2292237893 |
| 19 | 7264134169 |
| 20 | 22954663973 |
| 21 | 72350776321 |
| 22 | 227512682165 |
| 23 | 713919106105 |
| 24 | 2235900497141 |
| 25 | 6990131027905 |
| 26 | 21817681693157 |
[1,5,25,101,385,1397,4921,16949,57409,191909, 634777,2081477,6775873,21921941,70548793, 225995285,721032577,2292237893,7264134169, 22954663973,72350776321,227512682165,713919106105, 2235900497141,6990131027905,21817681693157] |