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Indices n of perfect squares n^2 which are neither the sum nor the difference of two primes.
2

%I #9 Mar 12 2015 22:14:06

%S 11,17,23,25,31,41,51,53,59,65,67,73,79,83,85,87,91,95,97,101,109,113,

%T 115,125,129,133,137,141,143,149,151,153,157,159,163,165,167,175,179,

%U 181,185,187,189,193,195,197,199,201,203,207,209,213,215,221,227,229

%N Indices n of perfect squares n^2 which are neither the sum nor the difference of two primes.

%F a(n) = sqrt(A106573(n)).

%e a(2)=17 because the second square which is nor the sum nor the difference of two primes (289=17^2) is the 17th one in the succession of the perfect squares (thus: index 17).

%Y Cf. A106544-A106548, A106562-A106564, A106571, A106573-A106575, A106577.

%K easy,nonn

%O 1,1

%A _Alexandre Wajnberg_, May 09 2005

%E Corrected and extended by _Ray Chandler_, May 12 2005