A202626 Order of Fibonacci group F(n,4) (or 0 if the group is infinite).

0, 5, 0, 3, 624, 125, 0, 7, 6560, 4905, 0, 11, 28560, 104845, 0, 15, 83520, 2236945, 0, 19, 194480, 43997205, 0, 23, 390624, 839065625, 0, 27, 707280, 15568306205, 0, 31, 1185920, 283472166945, 0, 35, 1874160, 5085221879845, 0, 39, 2825760, 90160039460905, 0, 43, 4100624, 1583296366510125, 0, 47, 5764800, 27584549361811505, 0, 51, 7890480

Offset

1,2

Comments

A column of the array described in A202624. See that entry for references.

Links

Table of n, a(n) for n=1..53.

Maple

g:=k->(4*k+1)*(2^(4*k+1)+(-1)^k*2^(2*k+1)+1);
f:=n-> if n mod 4 = 0 then n-1 elif n mod 4 = 1 then n^4-1 elif n mod 4 = 2 then g((n-2)/4); else 0; fi;
[seq(f(n), n=1..60)];

Crossrefs

Cf. A202624. A202628 is a subsequence.

Sequence in context: A300728 A321418 A225424 * A011995 A258754 A175296

Adjacent sequences: A202623 A202624 A202625 * A202627 A202628 A202629

Keyword

nonn

Author

N. J. A. Sloane, Dec 30 2011

Status

approved