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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 2 |
| 2 | 7 |
| 3 | 23 |
| 4 | 84 |
| 5 | 301 |
| 6 | 1127 |
| 7 | 4186 |
| 8 | 15891 |
| 9 | 60128 |
| 10 | 230334 |
| 11 | 881299 |
| 12 | 3397561 |
| 13 | 13095693 |
| 14 | 50725377 |
| 15 | 196537671 |
| 16 | 764061552 |
| 17 | 2971863841 |
| 18 | 11587071431 |
| 19 | 45203638492 |
| 20 | 176663521046 |
| 21 | 690848304886 |
| 22 | 2705270950914 |
| 23 | 10599701885837 |
| 24 | 41576025457459 |
| 25 | 163167064273475 |
| 26 | 640912413492991 |
| 27 | 2518764831588455 |
[1,2,7,23,84,301,1127,4186,15891,60128,230334, 881299,3397561,13095693,50725377,196537671, 764061552,2971863841,11587071431,45203638492, 176663521046,690848304886,2705270950914, 10599701885837,41576025457459,163167064273475, 640912413492991,2518764831588455] |