OFFSET
0,2
LINKS
Seiichi Manyama, Table of n, a(n) for n = 0..4
FORMULA
a(n) = (G^(7^n) - (1 - G)^(7^n))/sqrt(5) where G = (1 + sqrt(5))/2.
a(n) = (2/sqrt(5))*cosh(7^n*arccosh(sqrt(5)/2)).
a(n+1) = 125*a(n)^7 - 175*a(n)^5 + 70*a(n)^3 - 7*a(n) with a(0) = 1. - Peter Bala, Nov 25 2022
MAPLE
A145234 := proc(n) combinat[fibonacci](7^n) ; end proc:
seq(A145234(n), n=1..3) ; # R. J. Mathar, Apr 01 2011
MATHEMATICA
G = (1 + Sqrt[5])/2; Table[Expand[(G^(7^n) - (1 - G)^(7^n))/Sqrt[5]], {n, 1, 6}]
(* Second program: *)
Table[Round[N[(2/Sqrt[5])*Cosh[7^n*ArcCosh[Sqrt[5]/2]], 1000]], {n, 1, 4}]
PROG
(Magma) [Fibonacci(7^n): n in [0..5]]; // Vincenzo Librandi, Apr 02 2011
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Artur Jasinski, Oct 05 2008
STATUS
approved