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Modulo Summations

Problem 326

Published on 26 February 2011 at 04:00 pm [Server Time]

Let an be a sequence recursively defined by: .

So the first 10 elements of an are: 1,1,0,3,0,3,5,4,1,9.

Let f(N,M) represent the number of pairs (p,q) such that:

It can be seen that f(10,10)=4 with the pairs (3,3), (5,5), (7,9) and (9,10).

You are also given that f(104,103)=97158.

Find f(1012,106).


Answer:
Confirmation Code:
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