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a(n) = number of times (n-1) occurs in the fundamental period of Fibonacci numbers modulo n.
3

%I #4 Jan 17 2014 11:11:44

%S 1,2,3,1,4,6,4,1,5,8,1,1,4,8,3,1,4,4,1,2,1,2,4,1,4,8,8,2,1,6,1,1,1,4,

%T 4,1,4,1,3,1,4,2,4,1,5,4,4,1,4,8,3,2,4,8,1,2,1,2,1,1,4,1,3,1,4,2,4,1,

%U 1,8,1,1,4,8,3,1,2,6,1,1,8,8,4,1,4,8

%N a(n) = number of times (n-1) occurs in the fundamental period of Fibonacci numbers modulo n.

%C a(n) = A128924(n,n).

%H Reinhard Zumkeller, <a href="/A235715/b235715.txt">Table of n, a(n) for n = 1..10000</a>

%o (Haskell)

%o a235715 1 = 1

%o a235715 n = f 1 ps 0 where

%o f 0 (1 : xs) z = z

%o f _ (x : xs) z = f x xs (z + 0 ^ (n - 1 - x))

%o ps = 1 : 1 : zipWith (\u v -> (u + v) `mod` n) (tail ps) ps

%Y Cf. A001176, A001175.

%K nonn

%O 1,2

%A _Reinhard Zumkeller_, Jan 17 2014