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 A292981 #28 Jan 05 2025 19:51:41
%S A292981 126,846,1260,3952,5382,8460,6368,8496,13808,10856,14595,17700,51952,
%T A292981 49308,53820,83142,62700,71145,73962,97712,107550,88730,108224,131100,
%U A292981 153176,168730,196650,203432,195408,287600,309776,306612,365700,332528,399592,419800
%N A292981 Larger of bi-unitary amicable pair.
%C A292981 Analogous to amicable numbers with bi-unitary sigma (A188999) instead of sigma (A000203).
%C A292981 Hagis found all the bi-unitary amicable pairs with smaller members below 10^6.
%C A292981 The smaller members are in A292980.
%C A292981 The terms are ordered according to their lesser counterparts.
%H A292981 Amiram Eldar, <a href="/A292981/b292981.txt">Table of n, a(n) for n = 1..6368</a> (all terms with lesser member below 2*10^11, from David Moews' site).
%H A292981 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 A292981 David Moews, <a href="http://djm.cc/amicable.html">Perfect, amicable and sociable numbers</a>.
%e A292981 3952 is in the sequence since A188999(3608) - 3608 = 3952 and A188999(3952) - 3952 = 3608.
%t A292981 fun[p_,e_]:=If[Mod[e,2]==1,(p^(e+1)-1)/(p-1),(p^(e+1)-1)/(p-1)-p^(e/2)];
%t A292981 bsigma[n_] := If[n==1,1,Times @@ (fun @@@ FactorInteger[n])]; Do[s = bsigma[n]; If[s > 2 n && bsigma[s - n] == s, Print[s-n]],{n,1,10000}] (* _Amiram Eldar_, Sep 29 2018 *)
%Y A292981 Cf. A002046, A188999, A292980.
%K A292981 nonn
%O A292981 1,1
%A A292981 _Amiram Eldar_, Sep 27 2017