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A112461
Absolute value of coefficient of term [x^(n-5)] in characteristic polynomial of maximum matrix A of size n X n, where n >= 5. Maximum matrix A(i,j) is MAX(i,j), where indices i and j run from 1 to n.
6
5, 59, 374, 1694, 6149, 19019, 52052, 129272, 296582, 636922, 1293292, 2502604, 4644094, 8306914, 14382544, 24188824, 39633715, 63428365, 99360690, 152642490, 230345115, 341940885, 499969860, 720854160, 1025884860, 1442409540, 2005251864, 2758398104
OFFSET
5,1
LINKS
T. D. Noe and Bruno Berselli, Table of n, a(n) for n = 5..1004
Index entries for linear recurrences with constant coefficients, signature (11,-55,165,-330,462,-462,330,-165,55,-11,1).
FORMULA
a(n) = ((9n+5)/10!) * Product_{i=-4..4} (n+i).
G.f.: x^5*(5+4*x)/(1-x)^11. - Colin Barker, Mar 28 2012
MATHEMATICA
Table[(9n+5)/10! Product[n+i, {i, -4, 4}], {n, 5, 40}] (* Harvey P. Dale, Apr 26 2019 *)
PROG
(Octave, MATLAB) for n=5:20 a = zeros(n); for i=1:n for j=1:n a(i, j) = max(i, j); end end b = poly(a); b(6) end
KEYWORD
nonn,easy
AUTHOR
Paul Max Payton, Sep 23 2005
EXTENSIONS
Offset changed from 1 to 5, formulas and b-file adapted by Bruno Berselli, Mar 29 2012
STATUS
approved