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 A144474 A triangle sequence of determinants: a(n)=If[Mod[n, 2] == 0, 1, If[Mod[n, 2] == 1, -1, 0]]; b(n,m)=If[m < n && Mod[n, 3] == 0, 0, If[m < n && Mod[n, 3] == 1, 0, If[m < n && Mod[n, 3] == 2 && Mod[n, 2] == 0, 1, If[m < n && Mod[n, 3] == 2 && Mod[n, 2] == 1, -1, If[m == n, -1, 0]]]]]; M={{a(m), b(n, m)}, {a(n), b(n, n)}}; t(n,m)=Det[M]. 0
 -1, -2, 0, -1, 1, -1, -1, 1, -1, 1, -2, 0, -2, 0, -2, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1, -1, -2, 0, -2, 0, -2, 0, -2, 0, -1, 1, -1, 1, -1, 1, -1, 1, -1, -1, 1, -1, 1, -1, 1, -1, 1, -1, 1 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Row sums are:{-1, -2, -1, 0, -6, 0, -1, -8, -1, 0}. LINKS FORMULA a(n)=If[Mod[n, 2] == 0, 1, If[Mod[n, 2] == 1, -1, 0]]; b(n,m)=If[m < n && Mod[n, 3] == 0, 0, If[m < n && Mod[n, 3] == 1, 0, If[m < n && Mod[n, 3] == 2 && Mod[n, 2] == 0, 1, If[m < n && Mod[n, 3] == 2 && Mod[n, 2] == 1, -1, If[m == n, -1, 0]]]]]; M={{a(m), b(n, m)}, {a(n), b(n, n)}}; t(n,m)=Det[M]. EXAMPLE {-1}, {-2, 0}, {-1, 1, -1}, {-1, 1, -1, 1}, {-2, 0, -2, 0, -2}, {-1, 1, -1, 1, -1, 1}, {-1, 1, -1, 1, -1, 1, -1}, {-2, 0, -2, 0, -2, 0, -2, 0}, {-1, 1, -1, 1, -1, 1, -1, 1, -1}, {-1, 1, -1, 1, -1, 1, -1, 1, -1, 1} MATHEMATICA Clear[a, b, t, n, m] a[n_] := If[Mod[n, 2] == 0, 1, If[Mod[n, 2] == 1, -1, 0]]; b[n, m_] := If[m < n && Mod[n, 3] == 0, 0, If[m < n && Mod[n, 3] == 1, 0, If[m < n && Mod[n, 3] == 2 && Mod[n, 2] == 0, 1, If[m < n && Mod[n, 3] == 2 && Mod[n, 2] == 1, -1, If[m == n, -1, 0]]]]]; M = {{a[m], b[n, m]}, {a[n], b[n, n]}}; t[n_, m_] := Det[M]; Table[Table[t[n, m], {m, 0, n - 1}], {n, 1, 10}]; Flatten[%] CROSSREFS Sequence in context: A327406 A336865 A262257 * A298602 A203949 A070200 Adjacent sequences:  A144471 A144472 A144473 * A144475 A144476 A144477 KEYWORD sign,uned AUTHOR Roger L. Bagula and Gary W. Adamson, Oct 10 2008 STATUS approved

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Last modified September 24 03:26 EDT 2021. Contains 347623 sequences. (Running on oeis4.)