OFFSET
1,6
COMMENTS
a(n) = 1 iff n prime or n prime^2: a(A000430(n))=1.
LINKS
Antti Karttunen, Table of n, a(n) for n = 1..2048
EXAMPLE
n=12: (1,1,12), (1,2,6), (1,3,4), (2,2,3): therefore a(12)=4;
n=18: (1,1,18), (1,2,9), (1,3,6): therefore a(18)=3.
PROG
(PARI) A088433(n) = { my(s=0); fordiv(n, u, for(v=u, n-1, for(w=v+1, n, if(u*v*w==n, s++)))); (s); }; \\ Antti Karttunen, Aug 24 2017
CROSSREFS
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Oct 01 2003
STATUS
approved