A226325 - OEIS

A226325

Integers of the form n/tau(n)^2 as n runs through the integers, where tau(n) is the number of divisors of n.

1, 1, 2, 25, 3, 2, 5, 9, 25, 81, 6, 4, 16, 3, 5, 28, 36, 12, 128, 81, 81, 24, 7, 40, 8, 21, 28, 50, 12, 11, 16, 12, 96, 49, 13, 35, 44, 2401, 52, 45, 17, 36, 19, 160, 225, 68, 63, 23, 76, 30, 28, 36, 72, 21, 224, 92, 29, 77, 121, 31, 18, 27, 30, 91, 99, 116, 128, 37, 124

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OFFSET

1,3

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..10000

FORMULA

a(n) = A046754(n) / A000005(A046754(n))^2.

EXAMPLE

A046754(3) = 128, A000005(128) = 8, so a(3) = 128 / 8^2 = 2.

MAPLE

for n from 1 to 1000000 do

r := n/(numtheory[tau](n))^2 ;