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Quasiamicable Pair


Let sigma(m) be the divisor function of m. Then two numbers m and n are a quasiamicable pair if

 sigma(m)=sigma(n)=m+n+1.

The first few are (48, 75), (140, 195), (1050, 1925), (1575, 1648), ... (OEIS A005276). Quasiamicable numbers are sometimes called betrothed numbers or reduced amicable pairs.


See also

Amicable Pair

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References

Beck, W. E. and Najar, R. M. "More Reduced Amicable Pairs." Fib. Quart. 15, 331-332, 1977.Guy, R. K. "Quasi-Amicable or Betrothed Numbers." §B5 in Unsolved Problems in Number Theory, 2nd ed. New York:Springer-Verlag, pp. 59-60, 1994.Hagis, P. and Lord, G. "Quasi-Amicable Numbers." Math. Comput. 31, 608-611, 1977.Sloane, N. J. A. Sequence A005276/M5291 in "The On-Line Encyclopedia of Integer Sequences."

Referenced on Wolfram|Alpha

Quasiamicable Pair

Cite this as:

Weisstein, Eric W. "Quasiamicable Pair." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/QuasiamicablePair.html

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