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Table of n, a(n) for n=1..64.
for n>=43 a(n) = 2n-4
(PARI) a(n)=sum(i=1, n, sum(j=1, i, if(sign(1/i+1/j+1/n-1/2)-1, 0, 1)))
Sequence in context: A233774 A175313 A080518 * A168101 A027920 A033438
Adjacent sequences: A078591 A078592 A078593 * A078595 A078596 A078597
Benoit Cloitre, Dec 08 2002