|
|
A306328
|
|
If n = Product (p_j^k_j) then a(n) = Sum (p_j)^Product (k_j).
|
|
1
|
|
|
0, 2, 3, 4, 5, 5, 7, 8, 9, 7, 11, 25, 13, 9, 8, 16, 17, 25, 19, 49, 10, 13, 23, 125, 25, 15, 27, 81, 29, 10, 31, 32, 14, 19, 12, 625, 37, 21, 16, 343, 41, 12, 43, 169, 64, 25, 47, 625, 49, 49, 20, 225, 53, 125, 16, 729, 22, 31, 59, 100, 61, 33, 100, 64, 18, 16, 67, 361, 26, 14, 71, 15625, 73, 39, 64
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
1,2
|
|
LINKS
|
|
|
FORMULA
|
|
|
EXAMPLE
|
a(12) = a(2^2 * 3^1) = (2 + 3)^(2 * 1) = 25.
|
|
MATHEMATICA
|
Table[DivisorSum[n, # &, PrimeQ[#] &]^DivisorSigma[0, n/Last[Select[Divisors[n], SquareFreeQ]]], {n, 75}]
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|