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%I #21 Oct 02 2014 02:52:49
%S 1,9,21,37,69,97,137,177,225,293,349,421,489,577,665,749,861,973,1085,
%T 1201,1313,1457,1597,1741,1885,2053,2217,2377,2561,2733,2933,3125,
%U 3313,3521,3745,3969,4197,4421,4669,4905,5169,5417
%N a(n)=number of Gaussian integers z=a+bi satisfying |z|<=n+1/2.
%H Robert Israel, <a href="/A036704/b036704.txt">Table of n, a(n) for n = 0..10000</a>
%H Clive Tooth, <a href="/A036704/a036704.txt">A selection of a(n) values for n up to 10^9</a>
%H <a href="/index/Ga#gaussians">Index entries for Gaussian integers and primes</a>
%F a(n) = A057655(n^2+n). - _Robert Israel_, Sep 29 2014
%Y Cf. A057655.
%K nonn
%O 0,2
%A _Clark Kimberling_