A122191 - OEIS

A122191

Triangle read by rows: T(n,m) = number of positive divisors of m that are coprime to n.

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

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OFFSET

1,5

LINKS

Table of n, a(n) for n=1..105.

MATHEMATICA

Flatten@Table[ Count[GCD[Divisors[m], n], 1], {n, 14}, {m, n}] (* Ray Chandler, Aug 29 2006 *)

PROG

(PARI) A122191(n, m) = {local(s); s=0; fordiv(m, d, s=s+(gcd(d, n)==1)); s} \\ Michael B. Porter, Mar 01 2010

CROSSREFS

Cf. A116477.

Sequence in context: A109706 A174541 A029444 * A097847 A275120 A144379