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A158234 Coefficients of powers of two Hadamard characteristic polynomials: M(n)=Hadamard[2^n] except for 12. 1
1, 0, 1, -2, 0, 1, -16, -8, 0, 2, 1, -4096, -3072, -1792, -448, 0, 56, 28, 6, 1, -2985984, -2488320, -1824768, -760320, -253440, -46464, 0, 3872, 1760, 440, 88, 10, 1, 4294967296, 0, 671088640, 0, 29360128, 0, -2752512, 0, -344064, 0, -10752, 0, 448 (list; table; graph; refs; listen; history; text; internal format)
OFFSET
0,4
COMMENTS
Row sums are:
{1, 1, -1, -21, -9317, -8353125, 4992309225,...}.
The program uses an add on :
Hadamard.m
downloaded at: http://ftp2.de.freebsd.org/pub/math/mathematica/math-source/Applications/Mathematics/Applied/0205-760/Hadamard.m
This method gives random solutions for higher Hadamard matrices
without the matrix self-similar qualification.
Example matrix: Hadamard[12][[1]]={{1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1},
{1, -1, 1, 1, 1, -1, 1, -1, -1, 1, -1, -1},
{1, -1, -1, -1, 1, -1, 1, 1, 1, -1, -1, 1},
{1, -1, 1, -1, -1, -1, -1, 1, -1, 1, 1, 1},
{1, -1, -1, 1, -1, 1, 1, -1, -1, -1, 1, 1},
{1, 1, 1, 1, -1, -1, -1, -1, 1, -1, -1, 1},
{1, -1, -1, 1, -1, 1, -1, 1, 1, 1, -1, -1},
{1, 1, -1, -1, 1, 1, -1, -1, -1, 1, -1, 1},
{1, 1, -1, 1, 1, -1, -1, 1, -1, -1, 1, -1},
{1, -1, 1, -1, 1, 1, -1, -1, 1, -1, 1, -1},
{1, 1, 1, -1, -1, 1, 1, 1, -1, -1, -1, -1},
{ 1, 1, -1, -1, -1, -1, 1, -1, 1, 1, 1, -1}}
LINKS
FORMULA
M(n)=Hadamard[2^n] with 12 added;
out_(n,m)=coefficients(characteristicpolynomial(M(n),x),x).
EXAMPLE
{1},
{0, 1},
{-2, 0, 1},
{-16, -8, 0, 2, 1},
{-4096, -3072, -1792, -448, 0, 56, 28, 6, 1},
{-2985984, -2488320, -1824768, -760320, -253440, -46464, 0, 3872, 1760, 440, 88, 10, 1},
{4294967296, 0, 671088640, 0, 29360128, 0, -2752512, 0, -344064, 0, -10752, 0, 448, 0, 40, 0, 1}
MATHEMATICA
Needs["Hadamard`"];
Table[If[Hadamard[n] == {} && n >= 3, 0, If[n == 2, Hadamard[2], Hadamard[n][[1]]]], {n, 1, 10}];
a = Join[{1}, {x}, Union[ Table[CharacteristicPolynomial[If[Hadamard[n] == {} && n >= 3, 0, If[n == 2, Hadamard[2], Hadamard[n][[1]]]], x], {n, 2, 16}]]];
Table[CoefficientList[a[[n]], x], {n, 1, Length[a] - 1}];
Flatten[%]
Table[Apply[Plus, CoefficientList[a[[n]], x]], {n, 1, Length[a] - 1}];
CROSSREFS
Sequence in context: A328924 A217654 A267164 * A270882 A278778 A356817
KEYWORD
sign,tabl,uned,obsc
AUTHOR
Roger L. Bagula, Mar 14 2009
STATUS
approved

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Last modified March 28 20:05 EDT 2024. Contains 371254 sequences. (Running on oeis4.)