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A158390
A triangle of matrix polynomials: M(d)=Reverse[Table[If[ m <= n, m, 0], {n, 1, d}, {m, 1, d}]]*Transpose[Reverse[Table[If[ m <= n, m, 0], {n, 1, d}, {m, 1, d}]]].
0
1, 1, -1, -4, -1, 1, -36, 9, 5, -1, 576, 64, -61, -5, 1, 14400, -1600, -1045, 105, 14, -1, -518400, -32400, 29088, 1593, -385, -14, 1, -25401600, 1587600, 1079200, -63481, -11521, 579, 30, -1, 1625702400, 65028096, -55637056, -2062912, 523001, 16045
OFFSET
0,4
COMMENTS
Row sums are:
{1, 0, -4, -23, 575, 11873, -520517, -22809194, 1633567982, 122963894441,
-13226887049109,...}.
Example matrix:
M(3)={{1, 2, 3},
{2, 4, 0},
{3, 0, 0}}
FORMULA
M(d)=Reverse[Table[If[ m <= n, m, 0], {n, 1, d}, {m, 1, d}]]*Transpose[Reverse[Table[If[ m <= n, m, 0], {n, 1, d}, {m, 1, d}]]];
out_(n,m)=coefficients(characteristicpolynomial(M(n),x),x)
EXAMPLE
{1},
{1, -1},
{-4, -1, 1},
{-36, 9, 5, -1},
{576, 64, -61, -5, 1},
{14400, -1600, -1045, 105, 14, -1},
{-518400, -32400, 29088, 1593, -385, -14, 1},
{-25401600, 1587600, 1079200, -63481, -11521, 579, 30, -1},
{1625702400, 65028096, -55637056, -2062912, 523001, 16045, -1563, -30, 1},
{131681894400, -5267275776, -3616612416, 138811968, 28130697, -981153, -75500, 2167, 55, -1},
{-13168189440000, -365783040000, 301206312000, 7960416400, -2038537300, -48112905, 5258465, 99136, -4851, -55, 1}
MATHEMATICA
Clear[M, T, d, a, x, a0];
M[d_] :=Reverse[Table[If[ m <= n, m, 0], {n, 1, d}, {m, 1, d}]]*Transpose[Reverse[Table[If[ m <= n, m, 0], {n, 1, d}, {m, 1, d}]]];
a0 = Table[M[d], {d, 1, 10}];
Table[Det[M[d]], {d, 1, 10}];
Table[CharacteristicPolynomial[M[d], x], {d, 1, 10}];
Flatten[a]
Join[{1}, Table[Apply[Plus, CoefficientList[ Expand[CharacteristicPolynomial[M[n], x]], x]], {n, 1, 10}];
CROSSREFS
Sequence in context: A174412 A177939 A209196 * A228836 A176419 A299471
KEYWORD
sign,tabl
AUTHOR
STATUS
approved