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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.

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A102924 Real part of Gaussian amicable numbers in order of increasing magnitude. See A102925 for the imaginary part.

Original entry on oeis.org

-1105, -1895, -2639, -3235, -3433, -3970, -4694, -3549, -766, -4478, -6880, 5356, -6468, 8008, 4232, -8547
Offset: 1

Views

Author

T. D. Noe, Jan 19 2005

Keywords

Comments

For a Gaussian integer z, let the sum of the proper divisors be denoted by s(z) = sigma(z)-z, where sigma(z) is sum of the divisors of z, as defined by Spira for Gaussian integers. Then z is an amicable Gaussian number if z and s(z) are different and z = s(s(z)). The smallest Gaussian amicable number in the first quadrant is 8008+3960i.

Examples

			For z=-1105+1020i, we have s(z)=-2639-1228i and s(s(z))=z.

Links

Crossrefs

Cf. A102506 (Gaussian multiperfect numbers), A102531 (absolute Gaussian perfect numbers).

Programs

  • Mathematica
    s[z_Complex] := DivisorSigma[1, z]-z; nn=10000; lst={}; Do[d=a^2+b^2; If[d
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