a(n) = ((1 + 3*sqrt(2))*(4 + sqrt(2))^n + (1 - 3*sqrt(2))*(4 - sqrt(2))^n)/2.
A163615
a(n) = ((1 + 3*sqrt(2))*(4 + sqrt(2))^n + (1 - 3*sqrt(2))*(4 - sqrt(2))^n)/2.
Terms
- a(0) =1a(1) =10a(2) =66a(3) =388a(4) =2180a(5) =12008a(6) =65544a(7) =356240a(8) =1932304a(9) =10471072a(10) =56716320a(11) =307135552a(12) =1663055936a(13) =9004549760a(14) =48753614976a(15) =263965223168
External references
- oeis: A163615