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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 7 |
| 3 | 26 |
| 4 | 105 |
| 5 | 444 |
| 6 | 1944 |
| 7 | 8728 |
| 8 | 39999 |
| 9 | 186266 |
| 10 | 879108 |
| 11 | 4195762 |
| 12 | 20217136 |
| 13 | 98220992 |
| 14 | 480623748 |
| 15 | 2366735352 |
| 16 | 11720044199 |
| 17 | 58329063714 |
| 18 | 291607308864 |
| 19 | 1463803013168 |
| 20 | 7375252291592 |
| 21 | 37285645521840 |
| 22 | 189084169866584 |
| 23 | 961635234827346 |
| 24 | 4903573489214352 |
| 25 | 25065602340246704 |
| 26 | 128419743299166764 |
[1,2,7,26,105,444,1944,8728,39999,186266,879108, 4195762,20217136,98220992,480623748,2366735352, 11720044199,58329063714,291607308864, 1463803013168,7375252291592,37285645521840, 189084169866584,961635234827346,4903573489214352, 25065602340246704,128419743299166764] |