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A327168
Number of common divisors of n and A276086(n), with a(0) = 1.
4
1, 1, 1, 2, 1, 1, 1, 1, 1, 2, 2, 1, 1, 1, 1, 4, 1, 1, 1, 1, 2, 2, 1, 1, 1, 3, 1, 2, 1, 1, 1, 1, 1, 2, 1, 2, 1, 1, 1, 2, 2, 1, 2, 1, 1, 4, 1, 1, 1, 2, 3, 2, 1, 1, 1, 2, 2, 2, 1, 1, 1, 1, 1, 4, 1, 1, 1, 1, 1, 2, 4, 1, 1, 1, 1, 6, 1, 2, 1, 1, 2, 2, 1, 1, 2, 2, 1, 2, 1, 1, 1, 2, 1, 2, 1, 1, 1, 1, 3, 2, 2, 1, 1, 1, 1, 8
OFFSET
0,4
FORMULA
a(n) = A000005(A324198(n)).
a(n) = 1+A001222(A327167(n)) for n >= 1.
PROG
(PARI)
A276086(n) = { my(i=0, m=1, pr=1, nextpr); while((n>0), i=i+1; nextpr = prime(i)*pr; if((n%nextpr), m*=(prime(i)^((n%nextpr)/pr)); n-=(n%nextpr)); pr=nextpr); m; };
A327168(n) = numdiv(gcd(n, A276086(n)));
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Sep 19 2019
STATUS
approved