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Lpf_3(A242058(n)-3), where lpf_3(n) = lpf(n/3^t) (cf. A020639) such that 3^t (t>=0) is the maximal power of 3 which divides n.
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%I #16 Aug 21 2014 23:15:11

%S 1,5,1,11,5,17,7,1,29,5,13,41,5,7,17,5,19,59,5,23,71,5,7,1,5,29,7,5,

%T 11,101,5,107,37,5,7,11,5,43,5,137,5,7,149,5,7,5,13,19,5,59,179,5,7,

%U 191,5,197,5,11,5,7,13,5,227,7,5,79,239,1,5,13,83,5,7

%N Lpf_3(A242058(n)-3), where lpf_3(n) = lpf(n/3^t) (cf. A020639) such that 3^t (t>=0) is the maximal power of 3 which divides n.

%C An analog of A242034. Records are lesser numbers of twin primes.

%t lpf[n_]:=lpf[n]=First[First[FactorInteger[n]]];

%t lpf3[n_]:=lpf3[n]=If[#==1,1,lpf[#]]&[n/3^IntegerExponent[n,3]]

%t Map[lpf3[#-3]&,Select[Range[4,300,2],lpf3[#-1]>lpf3[#-3]&]](* _Peter J. C. Moses_, Aug 13 2014 *)

%Y Cf. A245024, A243937, A242057, A242058, A242059, A242033, A242034.

%K nonn

%O 1,2

%A _Vladimir Shevelev_, Aug 13 2014

%E More terms from _Peter J. C. Moses_, Aug 13 2014