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Triangle: let b(n) = 3*b(n - 1) - 2*b(n - 2) + b(n - 3), then T(n,m) = b(n) - b(m) - b(n - m) + 1.
0

%I #9 Dec 26 2022 08:56:17

%S 1,1,1,1,2,1,1,4,4,1,1,9,11,9,1,1,21,28,28,21,1,1,49,68,73,68,49,1,1,

%T 114,161,178,178,161,114,1,1,265,377,422,434,422,377,265,1,1,616,879,

%U 989,1029,1029,989,879,616,1,1,1432,2046,2307,2412,2440,2412,2307,2046

%N Triangle: let b(n) = 3*b(n - 1) - 2*b(n - 2) + b(n - 3), then T(n,m) = b(n) - b(m) - b(n - m) + 1.

%e {1},

%e {1, 1},

%e {1, 2, 1},

%e {1, 4, 4, 1},

%e {1, 9, 11, 9, 1},

%e {1, 21, 28, 28, 21, 1},

%e {1, 49, 68, 73, 68, 49, 1},

%e {1, 114, 161, 178, 178, 161, 114, 1},

%e {1, 265, 377, 422, 434, 422, 377, 265, 1},

%e {1, 616, 879, 989, 1029, 1029, 989, 879, 616, 1},

%e {1, 1432, 2046, 2307, 2412, 2440, 2412, 2307, 2046, 1432, 1}

%t b[0] := 0; b[1] := 1; b[2] := 3;

%t b[n_] := b[n] = 3*b[n - 1] - 2*b[n - 2] + b[n - 3];

%t t[n_, m_] := t[n, m] = b[n] - b[m] - b[n - m] + 1;

%t Table[Table[t[n, m], {m, 0, n}], {n, 0, 10}];

%t Flatten[%]

%Y Cf. A095263

%K nonn,tabl,easy

%O 0,5

%A _Roger L. Bagula_, Apr 18 2010