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| n | a(n) |
|---|---|
| 0 | 2 |
| 1 | 5 |
| 2 | 12 |
| 3 | 30 |
| 4 | 77 |
| 5 | 200 |
| 6 | 522 |
| 7 | 1365 |
| 8 | 3572 |
| 9 | 9350 |
| 10 | 24477 |
| 11 | 64080 |
| 12 | 167762 |
| 13 | 439205 |
| 14 | 1149852 |
| 15 | 3010350 |
| 16 | 7881197 |
| 17 | 20633240 |
| 18 | 54018522 |
| 19 | 141422325 |
| 20 | 370248452 |
| 21 | 969323030 |
| 22 | 2537720637 |
| 23 | 6643838880 |
| 24 | 17393796002 |
| 25 | 45537549125 |
| 26 | 119218851372 |
| 27 | 312119004990 |
| 28 | 817138163597 |
| 29 | 2139295485800 |
[2,5,12,30,77,200,522,1365,3572,9350,24477,64080, 167762,439205,1149852,3010350,7881197,20633240, 54018522,141422325,370248452,969323030,2537720637, 6643838880,17393796002,45537549125,119218851372, 312119004990,817138163597,2139295485800] |