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A225071
Number of Gaussian primes at taxicab distance 2n-1 from the origin.
3
0, 12, 16, 20, 16, 28, 24, 32, 32, 36, 24, 36, 64, 32, 48, 44, 32, 72, 64, 48, 72, 60, 56, 60, 40, 56, 72, 112, 64, 76, 88, 56, 136, 92, 80, 76, 88, 72, 64, 108, 72, 124, 160, 88, 112, 104, 64, 144, 112, 80, 144, 132, 80, 140, 128, 104, 160, 160, 104, 112, 136
OFFSET
1,2
COMMENTS
Except for 1+I, 1-I, -1+I, and -1-I, all Gaussian primes are an odd taxicab distance from the origin.
MATHEMATICA
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}]
CROSSREFS
Cf. A218858.
Sequence in context: A334584 A054281 A171955 * A210577 A231903 A364405
KEYWORD
nonn
AUTHOR
T. D. Noe, May 03 2013
STATUS
approved