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A098914
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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.
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0
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0, 0, 0, 8, 56, 512, 4816, 50336, 572096, 7048832, 93609984, 1333798272, 20304005760, 328957185024, 5652803666688, 102706725572096, 1967499023510528, 39636282097375232, 837750752009506816
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OFFSET
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3,4
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LINKS
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PROG
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(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
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), May 14 2007
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STATUS
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approved
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