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A306682
a(n) = gcd(sigma(n), pod(n)) where sigma(k) = the sum of the divisors of k (A000203) and pod(k) = the product of the divisors of k (A007955).
6
1, 1, 1, 1, 1, 12, 1, 1, 1, 2, 1, 4, 1, 4, 3, 1, 1, 3, 1, 2, 1, 4, 1, 12, 1, 2, 1, 56, 1, 72, 1, 1, 3, 2, 1, 1, 1, 4, 1, 10, 1, 48, 1, 4, 3, 4, 1, 4, 1, 1, 9, 2, 1, 24, 1, 8, 1, 2, 1, 24, 1, 4, 1, 1, 1, 144, 1, 2, 3, 16, 1, 3, 1, 2, 1, 4, 1, 24, 1, 2, 1, 2, 1
OFFSET
1,6
COMMENTS
See A324527(n) = the smallest numbers k such that a(k) = n.
FORMULA
a(n) = 1 for numbers in A014567.
a(n) = tau(n) for numbers in A324526.
EXAMPLE
For n=6: a(6) = gcd(tau(6), pod(6)) = gcd(4, 36) = 4.
PROG
(Magma) [GCD(SumOfDivisors(n), &*[d: d in Divisors(n)]): n in [1.. 100]]
(PARI) a(n) = my(d=divisors(n)); gcd(vecsum(d), vecprod(d)); \\ Michel Marcus, Mar 05 2019
KEYWORD
nonn
AUTHOR
Jaroslav Krizek, Mar 05 2019
STATUS
approved