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A242037
a(n) is the smallest k such that in the interval [1,k] of sequence A242034 all odd primes <= prime(n) are present.
4
1, 2, 23, 23, 63, 63, 120, 228, 228, 386, 460, 460, 602, 896, 1096, 1096, 1416, 1416, 1416, 3158, 3158, 3158, 3204, 3438, 3438, 3966, 3966, 3966, 8229, 8229, 8229, 8229, 8229, 8229, 8229, 8229, 8229, 8294, 8593, 8593, 11125, 11125, 11559, 11559, 12216, 13594
OFFSET
2,2
MATHEMATICA
lpf[n_]:=lpf[n]=First[First[FactorInteger[n]]]; (* least prime factor *)
A242034=Map[lpf[#-3]&, Select[Range[6, 100000, 2], lpf[#-1]>lpf[#-3]&](*A243937*)];
pos={}; NestWhile[#+1&, 2, (AppendTo[pos, Position[A242034, Prime[#], 1, 1]]; !Last[pos]=={})&];
A242037=Rest[FoldList[Max, -Infinity, Flatten[pos]]] (* Peter J. C. Moses, Aug 14 2014 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Vladimir Shevelev, Aug 12 2014
EXTENSIONS
More terms from Peter J. C. Moses, Aug 12 2014
STATUS
approved