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| n | a(n) |
|---|---|
| 1 | 1 |
| 2 | 3 |
| 3 | 4 |
| 4 | 9 |
| 5 | 20 |
| 6 | 38 |
| 7 | 78 |
| 8 | 157 |
| 9 | 319 |
| 10 | 630 |
| 11 | 1262 |
| 12 | 2525 |
| 13 | 5055 |
| 14 | 10121 |
| 15 | 20260 |
| 16 | 40560 |
| 17 | 81199 |
| 18 | 162242 |
| 19 | 324486 |
| 20 | 648973 |
| 21 | 1297951 |
| 22 | 2595913 |
| 23 | 5191844 |
| 24 | 10383728 |
| 25 | 20767535 |
| 26 | 41535232 |
| 27 | 83070775 |
| 28 | 166142182 |
| 29 | 332285627 |
| 30 | 664573784 |
| 31 | 1329152634 |
| 32 | 2658315407 |
| 33 | 5316651114 |
| 34 | 10633261669 |
| 35 | 21266523340 |
| 36 | 42533046681 |
| 37 | 85066093367 |
| 38 | 170132186745 |
[1,3,4,9,20,38,78,157,319,630,1262,2525,5055, 10121,20260,40560,81199,162242,324486,648973, 1297951,2595913,5191844,10383728,20767535, 41535232,83070775,166142182,332285627,664573784, 1329152634,2658315407,5316651114,10633261669, 21266523340,42533046681,85066093367,170132186745] |