A225071 - OEIS

%I #3 May 03 2013 18:55:39

%S 0,12,16,20,16,28,24,32,32,36,24,36,64,32,48,44,32,72,64,48,72,60,56,

%T 60,40,56,72,112,64,76,88,56,136,92,80,76,88,72,64,108,72,124,160,88,

%U 112,104,64,144,112,80,144,132,80,140,128,104,160,160,104,112,136

%N Number of Gaussian primes at taxicab distance 2n-1 from the origin.

%C Except for 1+I, 1-I, -1+I, and -1-I, all Gaussian primes are an odd taxicab distance from the origin.

%H T. D. Noe, <a href="/A225071/b225071.txt">Table of n, a(n) for n = 1..10000</a>

%t Table[cnt = 0; Do[If[PrimeQ[n - i + I*i, GaussianIntegers -> True], cnt++], {i, 0, n}]; Do[If[PrimeQ[i - n + I*i, GaussianIntegers -> True], cnt++], {i, n - 1, 0, -1}]; Do[If[PrimeQ[i - n - I*i, GaussianIntegers -> True], cnt++], {i, 1, n}]; Do[If[PrimeQ[n - i - I*i, GaussianIntegers -> True], cnt++], {i, n - 1, 1, -1}]; cnt, {n, 1, 200, 2}]

%Y Cf. A218858.

%K nonn

%O 1,2

%A _T. D. Noe_, May 03 2013