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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 4 |
| 3 | 13 |
| 4 | 34 |
| 5 | 80 |
| 6 | 174 |
| 7 | 359 |
| 8 | 712 |
| 9 | 1371 |
| 10 | 2580 |
| 11 | 4768 |
| 12 | 8684 |
| 13 | 15629 |
| 14 | 27852 |
| 15 | 49225 |
| 16 | 86390 |
| 17 | 150704 |
| 18 | 261530 |
| 19 | 451795 |
| 20 | 777360 |
| 21 | 1332791 |
| 22 | 2277864 |
| 23 | 3882048 |
| 24 | 6599064 |
| 25 | 11191705 |
| 26 | 18940564 |
| 27 | 31992709 |
| 28 | 53943562 |
| 29 | 90807056 |
| 30 | 152631750 |
| 31 | 256190783 |
[1,4,13,34,80,174,359,712,1371,2580,4768,8684, 15629,27852,49225,86390,150704,261530,451795, 777360,1332791,2277864,3882048,6599064,11191705, 18940564,31992709,53943562,90807056,152631750, 256190783] |