Location via proxy:   [ UP ]  
[Report a bug]   [Manage cookies]                
A112464
Absolute value of coefficient of term [x^(n-8)] in characteristic polynomial of maximum matrix A of size n X n, where n >= 8. Maximum matrix A(i,j) is MAX(i,j), where indices i and j run from 1 to n.
6
8, 143, 1343, 8823, 45543, 196707, 739347, 2483547, 7599867, 21492097, 56794705, 141485305, 334639305, 755863605, 1638428805, 3422280285, 6912424485, 13541987610, 25799313210, 47907161610, 86882479530, 154161302130, 268050218130, 457369908930, 766795640130
OFFSET
8,1
LINKS
Vincenzo Librandi and Bruno Berselli, Table of n, a(n) for n = 8..10008
FORMULA
a(n) = ((15n+8)/16!) * Product_{i=-7..7} (n+i).
G.f.: x^8*(8+7*x)/(1-x)^17. - Harvey P. Dale, Jul 24 2011
MATHEMATICA
Table[(Times@@(n+Range[0, 14])(15n+113))/16!, {n, 30}] (* or *) CoefficientList[ Series[ (-8-7 x)/(-1+x)^17, {x, 0, 30}], x] (* Harvey P. Dale, Jul 24 2011 *)
PROG
(Octave, MATLAB) for n=8:20 a = zeros(n); for i=1:n for j=1:n a(i, j) = max(i, j); end end b = poly(a); b(9) end
KEYWORD
easy,nonn
AUTHOR
Paul Max Payton, Sep 23 2005
EXTENSIONS
More terms from Harvey P. Dale, Jul 24 2011
Offset changed from 0 to 8, formulas and b-file adapted by Bruno Berselli, Mar 29 2012
STATUS
approved