cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Showing 1-1 of 1 results.

A332574 Numbers k such that k, k + 1 and k + 2 are all norm-deficient in Gaussian integers (A332572).

Original entry on oeis.org

127, 631, 751, 1327, 1527, 1687, 1711, 2031, 2047, 2487, 2647, 3207, 3271, 3351, 3511, 3831, 4567, 4791, 4911, 5127, 6007, 6087, 6711, 7431, 8247, 8367, 8391, 8407, 8551, 8751, 8871, 9031, 9447, 9991, 10407, 10551, 10887, 10927, 11631, 12471, 12567, 12631, 13807
Offset: 1

Views

Author

Amiram Eldar, Feb 16 2020

Keywords

Examples

			127 is a term since 127, 128 and 129 are all norm-deficient in Gaussian integers (A332572).
		

Crossrefs

Programs

  • Mathematica
    normDefQ[z_] := Abs[DivisorSigma[1, z, GaussianIntegers -> True]]^2 < 2*Abs[z]^2; Select[Range[10^4], AllTrue[# + Range[0, 2], normDefQ] &]
Showing 1-1 of 1 results.