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%I #3 Mar 30 2012 17:39:54
%S 1,1,1,1,6,1,1,18,18,1,1,36,48,36,1,1,60,90,90,60,1,1,90,144,162,144,
%T 90,1,1,126,210,252,252,210,126,1,1,168,288,360,384,360,288,168,1,1,
%U 216,378,486,540,540,486,378,216,1,1,270,480,630,720,750,720,630,480,270,1
%N Triangle T(n,m) read by rows: 1 in column m=0 and on the diagonal, else 3*n*m*(n-m).
%C Row sums are {1, 2, 8, 38, 122, 302, 632, 1178, 2018, 3242, 4952,...}.
%F T(n,m)= 1 if m=0 or n=m, else n^3-m^3-(n - m)^3 = 3*n*m*(n-m) =3*A157635(n,m).
%F Row sums: 2+A083374(n), n>0. - _R. J. Mathar_, Apr 10 2009
%e {1},
%e {1, 1},
%e {1, 6, 1},
%e {1, 18, 18, 1},
%e {1, 36, 48, 36, 1},
%e {1, 60, 90, 90, 60, 1},
%e {1, 90, 144, 162, 144, 90, 1},
%e {1, 126, 210, 252, 252, 210, 126, 1},
%e {1, 168, 288, 360, 384, 360, 288, 168, 1},
%e {1, 216, 378, 486, 540, 540, 486, 378, 216, 1},
%e {1, 270, 480, 630, 720, 750, 720, 630, 480, 270, 1}
%t t[n_, m_] = If[n*m*(n - m) == 0, 1, n^3 - (m^3 + (n - m)^3)];
%t Table[Table[t[n, m], {m, 0, n}], {n, 0, 10}];
%t Flatten[%]
%Y A141690
%K nonn,easy,tabl
%O 0,5
%A _Roger L. Bagula_, Mar 03 2009
%E Edited by the Associate Editors of the OEIS, Apr 10 2009
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