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A242034 a(n)=lpf(A243937(n)-3), where lpf = least prime factor (A020639). 9
3, 5, 3, 11, 3, 17, 3, 3, 29, 3, 5, 3, 41, 3, 3, 3, 59, 3, 5, 3, 71, 3, 7, 3, 3, 3, 5, 3, 101, 3, 107, 3, 3, 7, 3, 5, 3, 3, 137, 3, 3, 149, 3, 5, 3, 7, 3, 3, 3, 179, 3, 5, 3, 191, 3, 197, 3, 3, 11, 3, 5, 3, 13, 3, 227, 3, 3, 239, 3, 5, 3, 3, 3, 3, 269, 3, 5, 3 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The records of the sequence form sequence of lesser numbers of twin primes.

The sequence contains all odd primes. Cf. comment by R. Israel in A242033. - Vladimir Shevelev, Aug 16 2014

LINKS

Table of n, a(n) for n=1..78.

MATHEMATICA

lpf[n_]:=lpf[n]=First[First[FactorInteger[n]]]; (*lesat prime factor*)

A242034=Map[lpf[#-3]&, Select[Range[6, 300, 2], lpf[#-1]>lpf[#-3]&](*A243937*)] (* Peter J. C. Moses, Aug 14 2014 *)

CROSSREFS

Cf. A245024, A243937, A242033, A020639.

Sequence in context: A134061 A167221 A177930 * A205708 A309392 A089730

Adjacent sequences:  A242031 A242032 A242033 * A242035 A242036 A242037

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 October 19 15:50 EDT 2019. Contains 328223 sequences. (Running on oeis4.)