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A324644 a(n) = gcd(sigma(n), A276086(n)). 4
1, 3, 2, 1, 6, 1, 2, 15, 1, 9, 6, 1, 2, 3, 6, 1, 18, 1, 10, 3, 2, 9, 6, 5, 1, 3, 10, 1, 30, 1, 2, 21, 6, 9, 6, 7, 2, 15, 14, 45, 42, 1, 2, 21, 6, 9, 6, 1, 1, 3, 6, 7, 18, 5, 2, 15, 10, 45, 30, 7, 2, 3, 2, 1, 42, 1, 2, 21, 6, 9, 18, 5, 2, 3, 2, 35, 6, 7, 10, 3, 1, 63, 42, 7, 2, 3, 30, 45, 90, 1, 14, 21, 2, 9, 6, 7, 98, 3, 6, 7, 6, 1, 2, 105, 6 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Antti Karttunen, Table of n, a(n) for n = 1..30030

FORMULA

a(n) = gcd(A000203(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; };

A324644(n) = gcd(sigma(n), A276086(n));

CROSSREFS

Cf. A000203, A009194, A276086, A324534, A324645, A324646.

Sequence in context: A318254 A002130 A089145 * A134199 A323417 A102189

Adjacent sequences:  A324641 A324642 A324643 * A324645 A324646 A324647

KEYWORD

nonn

AUTHOR

Antti Karttunen, Mar 11 2019

STATUS

approved

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Last modified December 10 12:15 EST 2019. Contains 329895 sequences. (Running on oeis4.)