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%I #36 Jan 02 2014 12:31:21
%S 2,3,7,8,12,13,17,18,22,23,27,28,32,33,37,38,42,43,47,48,50,52,53,57,
%T 58,62,63,67,68,72,73,75,77,78,82,83,87,88,92,93,97,98,102,103,107,
%U 108,112,113,117,118,122,123,127,128,132,133,137,138,142,143,147,148,152,153,157,158
%N Values of n such that numbers of the form x^2+n*y^2 for some integers x, y cannot have prime factor of 5 raised to an odd power.
%C Equivalently, this sequence is the union of numbers of the form 25^n*(5*n+2) and numbers of the form 25^n*(5*n+3).
%F a(n) = 2.4 n + O(log n). - _Charles R Greathouse IV_, Dec 19 2013
%o (PARI) is(n)=n/=25^valuation(n, 25); n%5==2||n%5==3 \\ _Charles R Greathouse IV_ and _V. Raman_, Dec 19 2013
%Y Cf. A055046, A055047, A233999.
%K nonn,easy
%O 1,1
%A _V. Raman_, Dec 18 2013