%I #22 Aug 06 2023 02:36:56
%S 660,1092,4080,3420,6072,7800,9828,14880,32736,25308,51888,58800,
%T 74412,194472,265680,456288,612468,1024128,2097024,2165292,3594432,
%U 7174332,8487168,28090752,57750408,96049728,321367392
%N Orders of simple groups PSL(2,K) with exactly 4 prime divisors.
%C Sequence is conjectured to be infinite, see Bugeaud et al.
%C All entries are divisible by 6 by order formula for PSL(2,q).
%H Y. Bugeaud, Z. Cao, and M. Mignotte, <a href="https://doi.org/10.1006/jabr.2000.8742">On Simple K4-Groups</a>, Journal of Algebra, 241 (2001), 658-668.
%F Terms are q*(q^2-1)/gcd(2, q-1) for q in A364003.
%F a(n) = A033931(A364003(n)-1).
%e 660 has prime divisors 2,3,5,11.
%Y Subsequence of A352806. Elements generated from A364003.
%K nonn
%O 1,1
%A _Lixin Zheng_, Jul 03 2023
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