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 A302994 #16 Dec 05 2018 05:11:41
%S A302994 0,14,147,1553,15450,155395,1549818,15498814,155079196,1550331185,
%T A302994 15503061466,155037242668,1550370696100,15503650949671,
%U A302994 155036854371220,1550366484701654,15503648102080675
%N A302994 Number of bi-unitary abundant numbers < 10^n.
%F A302994 Conjecture: Lim_{n->oo} a(n)/10^n = 0.15... is the density of bi-unitary abundant numbers.
%t A302994 f[n_] := Select[Divisors[n], Function[d, CoprimeQ[d, n/d]]]; bsigma[m_] :=
%t A302994 DivisorSum[m, # &, Last@Intersection[f@#, f[m/#]] == 1 &]; babQ[n_] := bsigma[n] > 2 n; c = 0; k = 1; seq={}; Do[While[k < 10^n, If[babQ[k], c++]; k++]; AppendTo[seq, c], {n, 1, 5}]; seq
%o A302994 (PARI) biusigma(n) = {f = factor(n); for (i=1, #f~, p = f[i, 1]; e = f[i, 2]; f[i, 1] = if (e % 2, (p^(e+1)-1)/(p-1), (p^(e+1)-1)/(p-1) -p^(e/2)); f[i, 2] = 1; ); factorback(f); }
%o A302994 a(n) = sum(k=1, 10^n-1, biusigma(k) > 2*k); \\ _Michel Marcus_, Apr 17 2018
%Y A302994 Cf. A188999, A292982, A302992.
%K A302994 nonn,more
%O A302994 1,2
%A A302994 _Amiram Eldar_, Apr 17 2018
%E A302994 a(8)-a(17) from _Hiroaki Yamanouchi_, Aug 24 2018