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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.

A343402 Numbers k such that A260815(k) > A260815(k-1)+1.

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%I A343402 #11 Apr 14 2021 08:57:07
%S A343402 3,4,23,29,39,1559,1593,2435519,2435534,2485805,2485806,2485810,
%T A343402 2485827,2486989,5936893149287,5936893149290,5936949030071,
%U A343402 5936949030092,5936949030103,5936949030105,5936949030115,5936949030121,35246700334321411113125039,1242329884457453073932774588160466662938743561876559
%N A343402 Numbers k such that A260815(k) > A260815(k-1)+1.
%e A343402 a(3) = 23 is in the sequence because A260815(23) - A260815(22) = 575 - 46 > 1.
%p A343402 G:= proc(nv)
%p A343402   local n,v,k,np;
%p A343402   n:= nv[1]; v:= nv[2];
%p A343402   k:= min(seq((-n-1) mod p, p = numtheory:-factorset(v-n-1)));
%p A343402   np:= n+k+1;
%p A343402   [np, v+k+igcd(np,v+k)^2]
%p A343402 end proc:
%p A343402 R:= 3: t:= [3,12]:
%p A343402 for i from 2 to 24 do
%p A343402   t:= G(t);
%p A343402   R:= R, t[1];
%p A343402 od:
%p A343402 R;
%t A343402 2 + Position[Differences @ Nest[Append[#1, #1[[-1]] + GCD[#2, #1[[-1]]]^2] & @@ {#, Length[#] + 2} &, {3}, 10000], _?(# > 1 &)] // Flatten (* _Amiram Eldar_, Apr 14 2021 after _Michael De Vlieger_ at A260815 *)
%Y A343402 Cf. A260815.
%K A343402 nonn
%O A343402 1,1
%A A343402 _Robert Israel_, Apr 13 2021