# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a242037 Showing 1-1 of 1 %I A242037 #17 Aug 19 2014 01:19:26 %S A242037 1,2,23,23,63,63,120,228,228,386,460,460,602,896,1096,1096,1416,1416, %T A242037 1416,3158,3158,3158,3204,3438,3438,3966,3966,3966,8229,8229,8229, %U A242037 8229,8229,8229,8229,8229,8229,8294,8593,8593,11125,11125,11559,11559,12216,13594 %N A242037 a(n) is the smallest k such that in the interval [1,k] of sequence A242034 all odd primes <= prime(n) are present. %t A242037 lpf[n_]:=lpf[n]=First[First[FactorInteger[n]]]; (* least prime factor *) %t A242037 A242034=Map[lpf[#-3]&,Select[Range[6,100000,2],lpf[#-1]>lpf[#-3]&](*A243937*)]; %t A242037 pos={};NestWhile[#+1&,2,(AppendTo[pos,Position[A242034,Prime[#],1,1]];!Last[pos]=={})&]; %t A242037 A242037=Rest[FoldList[Max,-Infinity,Flatten[pos]]] (* _Peter J. C. Moses_, Aug 14 2014 *) %Y A242037 Cf. A245024, A243937, A242033, A242034, A242036. %K A242037 nonn %O A242037 2,2 %A A242037 _Vladimir Shevelev_, Aug 12 2014 %E A242037 More terms from _Peter J. C. Moses_, Aug 12 2014 # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE