cp's OEIS Frontend

A377338 Numbers k such that A060715(k), the number of prime numbers between k and 2k exclusive, divides k.

%I A377338 #11 Nov 28 2024 10:59:20
%S A377338 2,3,4,5,6,8,9,12,20,24,28,36,40,50,65,114,168,174,186,210,216,228,
%T A377338 240,246,252,504,623,672,805,812,1328,1584,1608,1616,1680,1704,1736,
%U A377338 1784,1792,1800,1808,1832,1888,1904,1912,1944,1992,2016,5121,5427,13790,13800
%N A377338 Numbers k such that A060715(k), the number of prime numbers between k and 2k exclusive, divides k.
%e A377338 k = A060715(k) * q
%e A377338 2 = 1 * 2
%e A377338 3 = 1 * 3
%e A377338 4 = 2 * 2
%e A377338 5 = 1 * 5
%e A377338 6 = 2 * 3
%e A377338 8 = 2 * 4
%e A377338 9 = 3 * 3
%e A377338 12 = 4 * 3
%e A377338 20 = 4 * 5
%t A377338 Select[Range[2, 14000], Divisible[#, PrimePi[2*# - 1] - PrimePi[#]] &] (* _Amiram Eldar_, Oct 25 2024 *)
%Y A377338 Cf. A060715.
%K A377338 nonn
%O A377338 1,1
%A A377338 _Jean-Marc Rebert_, Oct 25 2024