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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 2 |
| 3 | 5 |
| 4 | 16 |
| 5 | 42 |
| 6 | 111 |
| 7 | 296 |
| 8 | 793 |
| 9 | 2130 |
| 10 | 5796 |
| 11 | 15788 |
| 12 | 43370 |
| 13 | 119711 |
| 14 | 332449 |
| 15 | 927748 |
| 16 | 2600623 |
| 17 | 7319908 |
| 18 | 20677806 |
| 19 | 58604898 |
| 20 | 166595953 |
| 21 | 474868192 |
| 22 | 1356904893 |
| 23 | 3885983995 |
| 24 | 11151740822 |
| 25 | 32062866197 |
| 26 | 92345080709 |
| 27 | 266390632933 |
[1,2,5,16,42,111,296,793,2130,5796,15788,43370, 119711,332449,927748,2600623,7319908,20677806, 58604898,166595953,474868192,1356904893, 3885983995,11151740822,32062866197,92345080709, 266390632933] |