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%I #3 Mar 30 2012 17:27:39
%S 0,1,4,0,3,5,0,3,1,6,1,4,8,13,7,0,0,6,6,15,8,0,3,5,0,3,17,9,1,1,5,10,
%T 13,27,19,10,0,0,6,6,3,10,30,21,11,0,0,8,3,15,22,6,33,23,12,1,1,1,1,7,
%U 7,19,1,36,25,13,0,3,5,0,0,21,33,15,50,39,27,14,0,0,0,0,15,8,12,30,10
%N Triangle T(j,k) = remainder when j-th triangular number is divided by k-th triangular number, for 2 < j and 1 < k < j.
%C For triangular numbers see A000217. The zero values T(j,1) have been omitted, so the first row consists of T(3,2). A072524(n) = sum(T(n,k), k = 2, ..., n-1) for n > 2.
%e a(0) = triangular(3) mod triangular(2) = 6 mod 3 = 0; a(2) = triangular(4) mod triangular(3) = 10 mod 6 = 4.
%o (PARI) for(j=3,15, for(k=2,j-1,print1(binomial(j+1,2)%binomial(k+1,2),",")))
%Y Cf. A000217, A072524.
%K easy,nonn,tabl
%O 0,3
%A _Klaus Brockhaus_, Aug 02 2002