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%I #36 Oct 06 2017 01:54:49
%S 0,2,4,8,13,16,26,38,46,50,56,71,74,120,136,176,193,214,330,355,482,
%T 574,668,839,890,996,1088,1223,1528,1920,2039,2224,2374,2646,3055,
%U 3120,3811,5010,5539,6208,6591,8566,9139,9690,12359,13894,14796,15331,16118,16558
%N Record numbers of unordered triples {a, b, c} of distinct positive integers from 1 to n such that a*b = c*n.
%C Record numbers of ordered triples {a, b, c} of positive integers such that a*b = c*n with c < a < b < n.
%F a(n) = A278648(A292431(n)).
%e There are 4 unordered triples {a, b, c} of distinct positive integers from 1 to 10 such that a*b = c*10:
%e {2, 5, 1}: 2*5 = 1*10 = 10;
%e {4, 5, 2}: 4*5 = 2*10 = 20;
%e {5, 6, 3}: 5*6 = 3*10 = 30;
%e {5, 8, 4}: 5*8 = 4*10 = 40.
%e This is more than any n < 10, so 4 is in this sequence.
%Y Records in A278648.
%Y Cf. A292431.
%K nonn
%O 1,2
%A _Bobby Jacobs_ and _Robert G. Wilson v_, Sep 30 2017
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