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Search: id:A019448
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| A019448 |
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Number of monomials in expansion of determinant of an n X n Hankel matrix [ t(i+j) ] in terms of its entries. |
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+0 2
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| 1, 2, 5, 16, 58, 231, 1016, 4782, 23653, 121727, 648611
(list; graph; listen)
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OFFSET
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1,2
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FORMULA
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with(linalg): A019448 := proc(n) local i, j, m; m := array(1..n, 1..n); for i from 1 to n do for j from 1 to n do m[i, j] := a[i+j] od od; nops([coeffs(det(m))]); end;
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MATHEMATICA
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f[n_] := Length@ Expand@ Det@ Table[t[i + j], {i, n}, {j, n}]; Do[ Print@ f@n, {n, 11}] - from Robert G. Wilson v Sep 17 2006
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CROSSREFS
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Sequence in context: A157612 A149978 A149979 this_sequence A000753 A007878 A019589
Adjacent sequences: A019445 A019446 A019447 this_sequence A019449 A019450 A019451
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KEYWORD
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nonn
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AUTHOR
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Herbert Wilf (wilf(AT)central.cis.upenn.edu)
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EXTENSIONS
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Maple program and 2 more terms from Jeffrey Shallit (shallit(AT)graceland.uwaterloo.ca), Jun 08 2000
a(10) and a(11) from Robert G. Wilson v Sep 17 2006
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