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A307893 a(n) = lcm(sigma(n), pod(n)) / n, where sigma (k) = the sum of divisors of k (A000203) and pod(n) = the product of divisors of k (A007955). 0
1, 3, 4, 14, 6, 6, 8, 120, 39, 90, 12, 1008, 14, 84, 120, 1984, 18, 4212, 20, 8400, 672, 198, 24, 69120, 155, 546, 1080, 784, 30, 27000, 32, 64512, 528, 918, 1680, 25474176, 38, 570, 2184, 576000, 42, 148176, 44, 40656, 52650, 828, 48, 164560896, 399, 232500 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

n divides lcm(sigma(n), pod(n)) for all n >= 1.

LINKS

Table of n, a(n) for n=1..50.

FORMULA

a(n) = A324529(n) / n.

EXAMPLE

For n=4: a(4) = lcm(sigma(4), pod(4))/4 = lcm(7, 8)/4 = 56/4 = 14.

PROG

(MAGMA) [LCM(SumOfDivisors(n), &*[d: d in Divisors(n)]) / n: n in [1.. 10^5]]

CROSSREFS

Cf. A000203, A007955, A324529.

Sequence in context: A294384 A216868 A082732 * A220846 A009286 A076663

Adjacent sequences:  A307890 A307891 A307892 * A307894 A307895 A307896

KEYWORD

nonn

AUTHOR

Jaroslav Krizek, May 03 2019

STATUS

approved

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Last modified April 1 02:24 EDT 2020. Contains 333153 sequences. (Running on oeis4.)