OFFSET
2,5
FORMULA
a(n) = number of m such that the sum of the proper divisors of m is n, ignoring m if m is the product of two different odd primes.
EXAMPLE
a(13)=1 because s(27)=1+3+9 and s(35)=1+5+7=13 however 35's factors 3 and 5 are a Goldbach partition, so 35 is not counted.
CROSSREFS
KEYWORD
nonn
AUTHOR
Nathan McNew (agreatnate(AT)yahoo.com), Mar 29 2005
STATUS
approved