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A324645
a(n) = gcd(d(n), A276086(n)), where d(n) gives the number of divisors (A000005).
2
1, 1, 2, 3, 2, 1, 2, 1, 3, 1, 2, 1, 2, 1, 2, 5, 2, 1, 2, 3, 2, 1, 2, 1, 1, 1, 2, 3, 2, 1, 2, 3, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 3, 6, 1, 2, 5, 1, 3, 2, 3, 2, 1, 2, 1, 2, 1, 2, 1, 2, 1, 6, 7, 2, 1, 2, 3, 2, 1, 2, 1, 2, 1, 6, 3, 2, 1, 2, 5, 5, 1, 2, 1, 2, 1, 2, 1, 2, 1, 2, 3, 2, 1, 2, 1, 2, 3, 6, 9, 2, 1, 2, 1, 2
OFFSET
1,3
LINKS
FORMULA
a(n) = gcd(A000005(n), A276086(n)).
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; };
A324645(n) = gcd(numdiv(n), A276086(n));
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Mar 11 2019
STATUS
approved