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| n | a(n) |
|---|---|
| 1 | 2 |
| 2 | 10 |
| 3 | 34 |
| 4 | 104 |
| 5 | 386 |
| 6 | 1380 |
| 7 | 4800 |
| 8 | 16794 |
| 9 | 58875 |
| 10 | 206084 |
| 11 | 721260 |
| 12 | 2525126 |
| 13 | 8840855 |
| 14 | 30952194 |
| 15 | 108366098 |
| 16 | 379400544 |
| 17 | 1328316102 |
| 18 | 4650549495 |
| 19 | 16281977271 |
| 20 | 57004611828 |
| 21 | 199578061611 |
| 22 | 698740003512 |
| 23 | 2446349057586 |
| 24 | 8564879222176 |
[2,10,34,104,386,1380,4800,16794,58875,206084, 721260,2525126,8840855,30952194,108366098, 379400544,1328316102,4650549495,16281977271, 57004611828,199578061611,698740003512, 2446349057586,8564879222176] |