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.
%I A292980 #30 Jan 05 2025 19:51:41
%S A292980 114,594,1140,3608,4698,5940,6232,7704,9520,10744,12285,13500,41360,
%T A292980 44772,46980,60858,62100,67095,67158,73360,79650,79750,105976,118500,
%U A292980 141664,142310,177750,185368,193392,217840,241024,298188,308220,308992,356408,399200
%N A292980 Smaller of bi-unitary amicable pair.
%C A292980 Analogous to amicable numbers with bi-unitary sigma (A188999) instead of sigma (A000203).
%C A292980 Hagis found all the bi-unitary amicable pairs with smaller members below 10^6.
%C A292980 The larger members are in A292981.
%H A292980 Amiram Eldar, <a href="/A292980/b292980.txt">Table of n, a(n) for n = 1..6368</a> (all terms below 2*10^11, from David Moews' site).
%H A292980 Peter Hagis, Jr., <a href="https://web.archive.org/web/2024*/https://www.fq.math.ca/Scanned/25-2/hagis.pdf">Bi-unitary amicable and multiperfect numbers</a>, Fibonacci Quarterly, Vol. 25, No. 2 (1987), pp. 144-150.
%H A292980 David Moews, <a href="http://djm.cc/amicable.html">Perfect, amicable and sociable numbers</a>.
%e A292980 3608 is in the sequence since A188999(3608) - 3608 = 3952 and A188999(3952) - 3952 = 3608.
%t A292980 fun[p_,e_]:=If[Mod[e,2]==1,(p^(e+1)-1)/(p-1),(p^(e+1)-1)/(p-1)-p^(e/2)];
%t A292980 bsigma[n_] := If[n==1,1,Times @@ (fun @@@ FactorInteger[n])]; Do[s = bsigma[n]; If[s > 2 n && bsigma[s - n] == s, Print[n]],{n,1,10000}] (* _Amiram Eldar_, Sep 29 2018 *)
%Y A292980 Cf. A002025, A188999, A292981.
%K A292980 nonn
%O A292980 1,1
%A A292980 _Amiram Eldar_, Sep 27 2017