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| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 3 |
| 2 | 12 |
| 3 | 51 |
| 4 | 229 |
| 5 | 1057 |
| 6 | 4973 |
| 7 | 23707 |
| 8 | 114084 |
| 9 | 552863 |
| 10 | 2693562 |
| 11 | 13177746 |
| 12 | 64682128 |
| 13 | 318329991 |
| 14 | 1570030555 |
| 15 | 7757317348 |
| 16 | 38384755215 |
| 17 | 190172212694 |
| 18 | 943178242919 |
| 19 | 4682003520932 |
| 20 | 23259791365273 |
| 21 | 115629962700026 |
| 22 | 575158307708094 |
| 23 | 2862364197846018 |
| 24 | 14251344892802178 |
| 25 | 70983481869982844 |
| 26 | 353679253984093680 |
[1,3,12,51,229,1057,4973,23707,114084,552863, 2693562,13177746,64682128,318329991,1570030555, 7757317348,38384755215,190172212694,943178242919, 4682003520932,23259791365273,115629962700026, 575158307708094,2862364197846018, 14251344892802178,70983481869982844, 353679253984093680] |