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 A055026 Number of Gaussian primes of successive norms (indexed by A055025). 4
 4, 8, 4, 8, 8, 8, 8, 8, 4, 8, 8, 8, 8, 8, 8, 8, 8, 4, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 4, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 4, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 4, 8, 8 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS These are the primes in the ring of integers a+bi, a and b rational integers, i = sqrt(-1). REFERENCES R. K. Guy, Unsolved Problems in Number Theory, A16. L. W. Reid, The Elements of the Theory of Algebraic Numbers, MacMillan, NY, 1910, see Chap. V. LINKS EXAMPLE There are 8 Gaussian primes of norm 5, +-1+-2i and +-2+-i, but only two inequivalent ones (2+-i). MATHEMATICA m = 32; Length /@ Split[Sort[Select[Flatten[Table[{a^2 + b^2, a + b*I}, {a, -m, m}, {b, -m, m}], 1], PrimeQ[#[[2]], GaussianIntegers -> True] & ]], #1[[1]] == #2[[1]] & ][[1 ;; 87]] (* Jean-François Alcover, Apr 08 2011 *) CROSSREFS Cf. A055025-A055029, A055664-... Sequence in context: A010713 A105398 A005883 * A205681 A059163 A091198 Adjacent sequences:  A055023 A055024 A055025 * A055027 A055028 A055029 KEYWORD nonn,easy,nice AUTHOR N. J. A. Sloane, Jun 09 2000 EXTENSIONS More terms from Reiner Martin (reinermartin(AT)hotmail.com), Jul 20 2001 STATUS approved

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Last modified January 17 12:18 EST 2020. Contains 330958 sequences. (Running on oeis4.)