OFFSET
1,4
LINKS
Robert Israel, Table of n, a(n) for n = 1..10000
Eric Weisstein's World of Mathematics, Divisor Product
Eric Weisstein's World of Mathematics, Proper divisors
FORMULA
EXAMPLE
a(6) = 36 because 6 has 3 proper divisors {1,2,3} and 1^2*2^2*3^2 = 36.
MAPLE
seq(n^(numtheory:-tau(n)-2), n=1..50); # Robert Israel, Nov 13 2016
MATHEMATICA
Table[n^(DivisorSigma[0, n] - 2), {n, 1, 50}]
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Ilya Gutkovskiy, Oct 19 2016
STATUS
approved