0,2

A145451(n)=(1/2)A006266(n)

a(n)=(1/2) ((1 + Sqrt[2])^(3^n) + (1 - Sqrt[2])^(3^n)) a[n+1]= 4 a[n]^3 + 3 a[n] a[0]=1 A145451(n)=(1/2)A006266(n)

1) Table[Simplify[Expand[(1/2) ((1 + Sqrt[2])^(3^n) + (1 - Sqrt[2])^(3^n))]], {n, 0, 5}]

2) a = {}; k = 1; Do[AppendTo[a, k]; k = 4 k^3 + 3 k, {n, 1, 6}]; a (*Artur Jasinski*)

A006266

Sequence in context: A159994 A119181 A152518 this_sequence A144676 A125537 A001424

Adjacent sequences: A145448 A145449 A145450 this_sequence A145452 A145453 A145454

nonn

Artur Jasinski (grafix(AT)csl.pl), Oct 10 2008