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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 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,2

LINKS

Table of n, a(n) for n=2..47.

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

Cf. A245024, A243937, A242033, A242034, A242036.

Sequence in context: A128365 A153654 A153656 * A233692 A084323 A131983

Adjacent sequences:  A242034 A242035 A242036 * A242038 A242039 A242040

KEYWORD

nonn

AUTHOR

Vladimir Shevelev, Aug 12 2014

EXTENSIONS

More terms from Peter J. C. Moses, Aug 12 2014

STATUS

approved

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Last modified May 21 18:43 EDT 2019. Contains 323444 sequences. (Running on oeis4.)