OFFSET
2,7
COMMENTS
LINKS
Amiram Eldar, Table of n, a(n) for n = 2..10000
FORMULA
a(A063948(n)) = 0.
EXAMPLE
a(8) = 2 since 8 is the sum of the proper unitary divisors of 10 (1 + 2 + 5) and 12 (1 + 3 + 4).
MATHEMATICA
us[1] = 0; us[n_] := Times @@ (1 + Power @@@ FactorInteger[n]) - n; m = 100; v = Table[0, {m}]; Do[u = us[k]; If[2 <= u <= m, v[[u]]++], {k, 1, m^2}]; Rest @ v
CROSSREFS
KEYWORD
nonn
AUTHOR
Amiram Eldar, Sep 05 2019
STATUS
approved