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A085807 Permanent of the symmetric n X n matrix A defined by A[i,j] = |i-j| for 1 <= i,j <= n. 7
1, 0, 1, 4, 64, 1152, 34372, 1335008, 69599744, 4577345152, 374491314176, 37154032517376, 4402467119882240, 613680867638476800, 99443966100565999872, 18534733913629064343552, 3937496200758879526977536, 945776134421421651222708224, 255043190756805184245158084608 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,4

LINKS

Vaclav Kotesovec, Table of n, a(n) for n = 0..32

MAPLE

with(LinearAlgebra):

a:= n-> `if`(n=0, 1, Permanent(Matrix(n, (i, j)-> abs(i-j)))):

seq(a(n), n=0..18);  # Alois P. Heinz, Nov 14 2016

PROG

(PARI) permRWNb(a)=n=matsize(a)[1]; if(n==1, return(a[1, 1])); sg=1; in=vectorv(n); x=in; x=a[, n]-sum(j=1, n, a[, j])/2; p=prod(i=1, n, x[i]); for(k=1, 2^(n-1)-1, sg=-sg; j=valuation(k, 2)+1; z=1-2*in[j]; in[j]+=z; x+=z*a[, j]; p+=prod(i=1, n, x[i], sg)); return(2*(2*(n%2)-1)*p) for(n=1, 22, a=matrix(n, n, i, j, abs(i-j)); print1(permRWNb(a)", ")) - Herman Jamke (hermanjamke(AT)fastmail.fm), May 14 2007

CROSSREFS

Cf. A085750, A204249, A278845, A278847.

Sequence in context: A013709 A139292 A152923 * A014729 A322519 A259272

Adjacent sequences:  A085804 A085805 A085806 * A085808 A085809 A085810

KEYWORD

nonn

AUTHOR

Yuval Dekel (dekelyuval(AT)hotmail.com), Jul 24 2003

EXTENSIONS

More terms from Vladeta Jovovic, Jul 26 2003

a(0)=1 prepended by Alois P. Heinz, Nov 14 2016

STATUS

approved

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Last modified March 26 00:20 EDT 2019. Contains 321478 sequences. (Running on oeis4.)