A242060 Lpf_3(A242058(n)-3), 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.

1, 5, 1, 11, 5, 17, 7, 1, 29, 5, 13, 41, 5, 7, 17, 5, 19, 59, 5, 23, 71, 5, 7, 1, 5, 29, 7, 5, 11, 101, 5, 107, 37, 5, 7, 11, 5, 43, 5, 137, 5, 7, 149, 5, 7, 5, 13, 19, 5, 59, 179, 5, 7, 191, 5, 197, 5, 11, 5, 7, 13, 5, 227, 7, 5, 79, 239, 1, 5, 13, 83, 5, 7

Offset

1,2

Comments

An analog of A242034. Records are lesser numbers of twin primes.

Links

Table of n, a(n) for n=1..73.

Mathematica

lpf[n_]:=lpf[n]=First[First[FactorInteger[n]]];
lpf3[n_]:=lpf3[n]=If[#==1, 1, lpf[#]]&[n/3^IntegerExponent[n, 3]]
Map[lpf3[#-3]&, Select[Range[4, 300, 2], lpf3[#-1]>lpf3[#-3]&]](* Peter J. C. Moses, Aug 13 2014 *)

Crossrefs

Cf. A245024, A243937, A242057, A242058, A242059, A242033, A242034.

Sequence in context: A238554 A067292 A131782 * A185953 A323359 A324036

Adjacent sequences: A242057 A242058 A242059 * A242061 A242062 A242063

Keyword

nonn

Author

Vladimir Shevelev, Aug 13 2014

Extensions

More terms from Peter J. C. Moses, Aug 13 2014

Status

approved