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| n | a(n) |
|---|---|
| 0 | 4 |
| 1 | 7 |
| 2 | 12 |
| 3 | 21 |
| 4 | 37 |
| 5 | 65 |
| 6 | 114 |
| 7 | 200 |
| 8 | 351 |
| 9 | 616 |
| 10 | 1081 |
| 11 | 1897 |
| 12 | 3329 |
| 13 | 5842 |
| 14 | 10252 |
| 15 | 17991 |
| 16 | 31572 |
| 17 | 55405 |
| 18 | 97229 |
| 19 | 170625 |
| 20 | 299426 |
| 21 | 525456 |
| 22 | 922111 |
| 23 | 1618192 |
| 24 | 2839729 |
| 25 | 4983377 |
| 26 | 8745217 |
| 27 | 15346786 |
| 28 | 26931732 |
| 29 | 47261895 |
| 30 | 82938844 |
| 31 | 145547525 |
| 32 | 255418101 |
| 33 | 448227521 |
| 34 | 786584466 |
[4,7,12,21,37,65,114,200,351,616,1081,1897,3329, 5842,10252,17991,31572,55405,97229,170625,299426, 525456,922111,1618192,2839729,4983377,8745217, 15346786,26931732,47261895,82938844,145547525, 255418101,448227521,786584466] |