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 A343185 #18 Apr 21 2021 01:53:43 %S A343185 2,3,4,5,6,7,8,9,10,12,14,15,16,18,19,30,33,34,35,36,40,44,45,46,56, %T A343185 60,70,76,80,92,100,112,114,128,130,140,145,148,182,184,209,210,221, %U A343185 228,238,247,270,276,286,297,324,344,372,399,408,410,425,429,437,444,460,468,475,504,506,507,510 %N A343185 Numbers k such that 2*k is a multiple of A045917(k). %H A343185 Robert Israel, <a href="/A343185/b343185.txt">Table of n, a(n) for n = 1..600</a> %e A343185 a(4) = 5 is a term because 2*5 = 10 is a multiple of A045917(5) = 2. %p A343185 P:= select(isprime, [2,seq(i,i=3..2000,2)]): %p A343185 filter:= proc(n) local k1, k2; %p A343185 k1:= ListTools:-BinaryPlace(P,n+1); %p A343185 k2:= ListTools:-BinaryPlace(P,2*n+1); %p A343185 2*n mod nops(convert(P[1..k1],set) intersect map(t -> 2*n-t, convert(P[k1..k2],set))) = 0 %p A343185 end proc: %p A343185 select(filter, [$2..1000]); %Y A343185 Cf. A045917. %K A343185 nonn %O A343185 1,1 %A A343185 _J. M. Bergot_ and _Robert Israel_, Apr 18 2021