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A027478 Triangle of the cube of the normalized, unsigned Stirling matrix of the first kind. 7

%I #11 Jan 20 2019 06:32:33

%S 1,7,1,176,39,1,10746,2951,126,1,1297704,407450,22535,310,1,272866980,

%T 94128364,6139575,112435,645,1,91570835040,33910601508,2487385684,

%U 54814095,426475,1197,1,46034917019280,18030534782364,1446119232796,36402686929,345710680,1333906,2044,1

%N Triangle of the cube of the normalized, unsigned Stirling matrix of the first kind.

%C The absolute values are unchanged if one uses the signed Stirling numbers of the first kind.

%F Let A be the lower triangular matrix with entries a[ i, j ] = (-1)^(i+j)*s(i, j)/i! if j<=i, 0 if j>i, where s(i,j) is the Stirling number of the first kind. Let N be the column vector ((i!^3)).

%F T is the lower triangular matrix A.A.A.N.

%e The first rows of the triangle are :

%e 1,

%e 7, 1,

%e 176, 39, 1,

%e 10746, 2951, 126, 1,

%e 1297704, 407450, 22535, 310, 1,

%e 272866980, 94128364, 6139575, 112435, 645, 1,

%e ...

%t Module[{nmax=8,m},m=(Table[Table[(-1)^(i+j) StirlingS1[i,j]/i!,{j,1,nmax}],{i,1,nmax}]);m=m.m.m*Table[i!^3,{i,1,nmax}]; Flatten[Table[Table[m[[i,j]],{j,1,i}],{i,1,nmax}],1]]

%Y Cf. A027477 for the quadratic version.

%Y Cf. A027479 for the quartic version.

%Y Cf. A027482 is the first subdiagonal of this triangle.

%K nonn,tabl,easy

%O 1,2

%A _Olivier Gérard_

%E Definition, formula and program edited for clarity by _Olivier Gérard_, Jan 20 2019

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Last modified April 24 14:23 EDT 2024. Contains 371960 sequences. (Running on oeis4.)