OFFSET
0,4
COMMENTS
Also omega of the product of products of parts over all integer partitions of n.
The omega of n is A001222(n), the number of prime factors of n counted with multiplicity.
EXAMPLE
The integer partitions of 5 are {(5), (4,1), (3,2), (3,1,1), (2,2,1), (2,1,1,1), (1,1,1,1,1)} with products {5,4,6,3,4,2,1} with product 2880 with omega 9, so a(5) = 9.
MATHEMATICA
Table[Plus@@PrimeOmega/@Join@@IntegerPartitions[n], {n, 0, 30}]
CROSSREFS
KEYWORD
nonn
AUTHOR
Gus Wiseman, May 08 2019
STATUS
approved