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%I #11 Jan 11 2024 16:18:12
%S 13,17,19,29,31,33,37,41,43,49,53,61,65,67,71,73,79,89,97,101,103,109,
%T 113,121,127,129,131,137,139,145,149,151,157,161,163,169,173,177,181,
%U 191,193,197,199,201,209,211,217,223,229,233,239,241,251,253,257,265,269,271,277,281,283,289,293,301,305,307,311,313
%N Numbers k > 1 for which bigomega(k) < bigomega(k-1)/2, where bigomega gives the number of prime factors, counted with multiplicity.
%H Antti Karttunen, <a href="/A339912/b339912.txt">Table of n, a(n) for n = 1..12313; all terms <= 65537</a>
%t Select[Range[3, 313, 2], PrimeOmega[#] < PrimeOmega[# - 1]/2 &] (* _Michael De Vlieger_, Dec 22 2020 *)
%t Flatten[Position[Partition[PrimeOmega[Range[400]],2,1],_?(#[[2]]<#[[1]]/2&),1,Heads->False]]+1 (* _Harvey P. Dale_, Jan 11 2024 *)
%o (PARI) isA339912(n) = ((n>1)&&((2*bigomega(n))<bigomega(n-1)));
%Y Cf. A001222.
%Y Subsequence of A339911 and of A339910.
%Y Cf. also A339908.
%K nonn
%O 1,1
%A _Antti Karttunen_, Dec 22 2020
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