

A260073


Number of triples {x, y, x mod y} of three distinct divisors of n.


5



0, 0, 0, 0, 0, 1, 0, 0, 0, 1, 0, 3, 0, 1, 0, 0, 0, 3, 0, 3, 1, 1, 0, 6, 0, 1, 0, 2, 0, 8, 0, 0, 0, 1, 0, 9, 0, 1, 1, 5, 0, 9, 0, 2, 0, 1, 0, 10, 0, 3, 0, 3, 0, 6, 1, 4, 1, 1, 0, 23, 0, 1, 2, 0, 0, 7, 0, 3, 0, 6, 0, 18, 0, 1
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OFFSET

1,12


COMMENTS



LINKS



EXAMPLE

a(6) = 1 because x = 3, y = 2, x mod y = 1 and 3, 2, 1 are distinct divisors of 6.


PROG

(PARI) a(n)=my(d=divisors(n), x, y, z); sum(i=2, #d2, y=d[i]; sum(j=i+1, #d1, x=d[j]; z=x%y; z && n%z==0)) \\ Charles R Greathouse IV, Aug 20 2015


CROSSREFS



KEYWORD

nonn


AUTHOR



EXTENSIONS



STATUS

approved



