A242066 The smallest even k such that lpf_3(k-3) > lpf_3(k-1) >= p_n, 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.
16, 22, 34, 40, 70, 70, 70, 112, 112, 112, 130, 130, 142, 160, 184, 184, 202, 214, 310, 310, 310, 310, 310, 310, 310, 340, 340, 340, 382, 412, 412, 490, 490, 490, 490, 490, 502, 544, 544, 544, 574, 580, 634, 634, 634, 754, 754, 754, 754, 754, 754, 754, 772
Offset: 3
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Mathematica
lpf[n_]:=lpf[n]=First[First[FactorInteger[n]]];(*least prime factor*) lpf3[n_]:=lpf3[n]=If[#==1,1,lpf[#]]&[n/3^IntegerExponent[n,3]]; Table[NestWhile[#+2&,2,!(lpf3[#-3]>lpf3[#-1]>=Prime[n])&],{n,3,100}] (* Peter J. C. Moses, Aug 14 2014 *)
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