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%I #6 Nov 01 2019 16:38:40
%S 1,0,0,0,0,0,0,0,0,0,121,0,0,0,0,0,289,0,0,0,0,0,529,0,625,0,0,0,0,0,
%T 961,0,0,0,0,0,0,0,1521,0,1681,0,0,0,2025,0,0,0,0,0,2601,0,2809,0,0,0,
%U 3249,0,3481,0,0,0,0,0,4225,0,4489,0,0,0,0,0,5329,0,0,0,0,0,6241,0,6561
%N Perfect squares n^2 which are not the sum of two primes (otherwise 0).
%C For odd n, n^2 is odd so the two primes must be opposite in parity. Lesser prime must be 2 and greater prime must be n^2-2. Thus for odd n, n^2 is the sum of two primes iff n^2-2 is prime. - _Ray Chandler_, May 12 2005
%F a(n) = n^2 - A106545(n).
%e a(10)=0 because 10^2=100=97+3 (sum of two primes)
%e a(11)=11^2=121, which is impossible to obtain summing two primes.
%Y Cf. A106545-A106548, A106562-A106564, A106571, A106573-A106575, A106577.
%K easy,nonn
%O 1,11
%A _Alexandre Wajnberg_, May 08 2005
%E Extended by _Ray Chandler_, May 12 2005
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