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A158452
A triangle sequence of permutation Hadamard {1,-1) matrix polynomials: M(d)=Table[If[ m == n, d!/n!, 0], {n, d}, {m, d}]; m(n)=M(2^n)*Hadamard(2^n)
0
1, 2, 2, 1, -1, 24, 24, 24, 24, 12, -12, 12, -12, 4, -4, -4, 4, 1, 1, -1, -1, 40320, 40320, 40320, 40320, 40320, 40320, 40320, 40320, 20160, -20160, -20160, -20160, 20160, 20160, -20160, 20160, 6720, 6720, -6720, -6720, -6720, -6720, 6720, 6720, 1680
OFFSET
0,2
COMMENTS
Row sums are:
{0, -4, -25078, -6495526469206231383391390,
286062680268501848545408513842882834075841335269461890307160415945609971775008
5331640349522681828065666242531221092072696301456782016,...}.
Example matrix:
m(2^2)={{24, 24, 24, 24},
{12, -12, 12, -12},
{4, -4, -4, 4},
{1, 1, -1, -1}}.
FORMULA
M(d)=Table[If[ m == n, d!/n!, 0], {n, d}, {m, d}];
m(n)=M(2^n)*Hadamard(2^n);
out_(n,m)=coefficients(characteristicpolynomial(m(n),x),x)
EXAMPLE
{1, -1},
{-4, -1, 1},
{-18432, -5952, -688, -7, 1},
MATHEMATICA
Needs["Hadamard`"];
M[d_] := Table[If[ m == n, d!/n!, 0], {n, d}, {m, d}];
a = Join[{{{1}}}, Table[M[2^n].If[Hadamard[2^n] == {} && 2^n >= 3, 0, If[2^n == 2, Hadamard[2], Hadamard[2^n][[1]]]], {n, 1, 4}]];
Table[CoefficientList[CharacteristicPolynomial[a[[n]], x], x], {n, 1, Length[ a]}];
Flatten[a]
Table[Apply[Plus, CoefficientList[CharacteristicPolynomial[a[[n]], x], x]], {n, 1, Length[a]}];
CROSSREFS
Sequence in context: A174120 A240939 A016739 * A208929 A039965 A300481
KEYWORD
sign,tabl,uned
AUTHOR
Roger L. Bagula, Mar 19 2009
STATUS
approved