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%I #17 Jan 19 2019 04:15:43
%S 27962,37145,39234,42182,50138,51986,58562,62643,64074,83082,84774,
%T 89089,95642,120783,123486,133903,134826,146165,149606,153543,159182,
%U 166495,170751,176754,177122,178086,178087,179330,180782,203433,207974,211562,212583,214489,219063,219894,219963,225069,228135
%N Start of a triple of consecutive squarefree numbers each of which has exactly 4 distinct prime factors.
%H Daniel C. Mayer, <a href="http://www.linkedin.com/groupItem?view=&gid=4510047&item=5873010790079934468&type=member">Define an "m-triple" to consist of three consecutive squarefree positive integers, each with exactly m prime divisors</a>, Number Theory group on LinkedIn.com
%e The two squarefree numbers following a(1)=27962, 27965 and 27966, also have 4 prime divisors just as a(1).
%t Transpose[Select[Partition[Select[Range[230000],SquareFreeQ],3,1], PrimeNu[ #] =={4,4,4}&]][[1]] (* _Harvey P. Dale_, Jul 06 2014 *)
%o (PARI) (back(n)=for(i=1,2,until(issquarefree(n--),));n);for(n=1,9999,issquarefree(n)||next;ndk==ndm&&omega(n)==ndm&&ndk==4&&print1(back(n)",");ndk=ndm;ndm=omega(n))
%Y See A242605-A242608 for squarefree triples with m = 2..5 prime factors; A242621 (first terms for positive m).
%K nonn
%O 1,1
%A _M. F. Hasler_, May 18 2014
%E Minor edit by _Hans Havermann_, Aug 19 2014
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