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.

A357609 Numbers k such that k, k+1, and k+2 are all in A357605.

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%I A357609 #9 Oct 09 2022 04:22:39
%S A357609 10667829248,14322877568,25929352448,26967189248,31315096448,
%T A357609 32186016224,35337613310,36312573374,41326711424,53162460350,
%U A357609 69405075584,71840196350,72806666750,73217757248,83103523424,106184935934,109302242048,111640866974,115294917374,116768901248
%N A357609 Numbers k such that k, k+1, and k+2 are all in A357605.
%C A357609 Numbers k such that A162296(k) > 2*k, A162296(k+1) > 2*(k+1), and A162296(k+2) > 2*(k+2).
%H A357609 Amiram Eldar, <a href="/A357609/b357609.txt">Table of n, a(n) for n = 1..209</a> (terms below 10^12)
%e A357609 10667829248 is a term since 10667829248, 10667829249 and 10667829250 are all in A357605: A162296(10667829248) = 21342038784 > 2*10667829248, A162296(10667829249) = 21798236160 > 2*10667829249 and A162296(10667829250) = 21810824640 > 2*10667829250.
%t A357609 q[n_] := Module[{f = FactorInteger[n], p, e}, p = f[[;; , 1]]; e = f[[;; , 2]]; Times @@ ((p^(e + 1) - 1)/(p - 1)) - Times @@ (p + 1) > 2*n]; v = Cases[Import["https://oeis.org/A096536/b096536.txt", "Table"], {_, _}][[;; , 2]]; s = {}; Do[n = v[[k]]; If[q[n] && q[n+1] && q[n+2], AppendTo[s, n]], {k, 1, Length[v]}]; s
%Y A357609 Cf. A162296.
%Y A357609 Subsequence of A013929, A096536, A357605 and A357608.
%K A357609 nonn
%O A357609 1,1
%A A357609 _Amiram Eldar_, Oct 06 2022