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A098914
Permanent of the n X n (0,1)-matrices with ij-th entry equal to zero iff it is on the diagonal, the first-upper diagonal, the main antidiagonal or the first-upper antidiagonal.
0
0, 0, 0, 8, 56, 512, 4816, 50336, 572096, 7048832, 93609984, 1333798272, 20304005760, 328957185024, 5652803666688, 102706725572096, 1967499023510528, 39636282097375232, 837750752009506816
OFFSET
3,4
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, 23, a=matrix(n, n, i, j, ((j-i)!=0)&&((j-i)!=1)&&((j+i)!=(n+1))&&((j+i)!=n)); print1(permRWNb(a)", ")) \\ Herman Jamke (hermanjamke(AT)fastmail.fm), May 14 2007
CROSSREFS
Sequence in context: A087290 A086787 A218125 * A009107 A209665 A208944
KEYWORD
nonn
AUTHOR
Simone Severini, Oct 17 2004
EXTENSIONS
More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), May 14 2007
STATUS
approved