A069859 - OEIS

The OEIS is supported by the many generous donors to the OEIS Foundation.

A069859

(Largest prime factor of n) modulo (smallest prime factor of n).

0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 1, 0, 1, 2, 0, 0, 1, 0, 1, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 0, 2, 1, 2, 1, 0, 1, 1, 1, 0, 1, 0, 1, 2, 1, 0, 1, 0, 1, 2, 1, 0, 1, 1, 1, 1, 1, 0, 1, 0, 1, 1, 0, 3, 1, 0, 1, 2, 1, 0, 1, 0, 1, 2, 1, 4, 1, 0, 1, 0, 1, 0, 1, 2, 1, 2, 1, 0, 1, 6, 1, 1, 1, 4, 1, 0, 1, 2, 1, 0, 1, 0, 1, 1

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

OFFSET

1,15

COMMENTS

a(n) = A006530(n) - A069897(n)*A020639(n).

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..65537

FORMULA

a(n) = A006530(n) mod A020639(n).

MATHEMATICA

lpfmspf[n_]:=Module[{fs=Transpose[FactorInteger[n]][[1]]}, Mod[Last[fs], First[fs]]]; Array[lpfmspf, 100] (* Harvey P. Dale, Jul 10 2015 *)

PROG