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.

A050972 Smaller member of friendly pairs ordered by smallest maximal element.

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%I A050972 #24 Feb 16 2025 08:32:41
%S A050972 6,30,80,40,12,84,66,78,102,6,28,114,240,138,120,150,174,135,186,864,
%T A050972 222,246,60,258,282,560,318,84,270,330,84,270,1488,354,366,720,390,
%U A050972 402,426,360,438,880,474,498,510,440,30,140,534,132,1040,570,582,606
%N A050972 Smaller member of friendly pairs ordered by smallest maximal element.
%C A050972 Conjecture: If a(n) is in A005153, then A050973(n) is in A005153. It is natural to ask if there exists a generalization of the indicator function for A005153, call it m(n), such that m(n) = 1 for n in A005153, 0 < m(n) < 1 otherwise, and m(a(n)) <= m(A050973(n)) for all n. See also A017666. - _Jaycob Coleman_, Sep 27 2014
%H A050972 Donovan Johnson, <a href="/A050972/b050972.txt">Table of n, a(n) for n = 1..10000</a>
%H A050972 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/FriendlyPair.html">Friendly Pair.</a>
%Y A050972 Cf. A050973 (larger member of pair), A074902 (friendly numbers).
%K A050972 nonn
%O A050972 1,1
%A A050972 _Eric W. Weisstein_