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%I #18 Apr 21 2021 01:53:43
%S 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 60,70,76,80,92,100,112,114,128,130,140,145,148,182,184,209,210,221,
%U 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 Numbers k such that 2*k is a multiple of A045917(k).
%H Robert Israel, <a href="/A343185/b343185.txt">Table of n, a(n) for n = 1..600</a>
%e a(4) = 5 is a term because 2*5 = 10 is a multiple of A045917(5) = 2.
%p P:= select(isprime, [2,seq(i,i=3..2000,2)]):
%p filter:= proc(n) local k1, k2;
%p k1:= ListTools:-BinaryPlace(P,n+1);
%p k2:= ListTools:-BinaryPlace(P,2*n+1);
%p 2*n mod nops(convert(P[1..k1],set) intersect map(t -> 2*n-t, convert(P[k1..k2],set))) = 0
%p end proc:
%p select(filter, [$2..1000]);
%Y Cf. A045917.
%K nonn
%O 1,1
%A _J. M. Bergot_ and _Robert Israel_, Apr 18 2021
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