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Search: id:A110950
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| A110950 |
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a(n) = permanent of an n X n matrix M of zeros and ones defined as follows: if we concatenate the rows of M to form a vector v of length n^2, v_i = 0 if i is prime and v_i = 1, otherwise. |
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+0
1
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| 1, 3, 12, 36, 383, 1560, 19162, 97680, 1804643, 4082400, 207316912, 1186043040, 25595629200, 266545072080, 6282386337194, 26013379392000, 1682187039875545, 11884755543091200, 396276417247253760, 5491416186030297600
(list; graph; listen)
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OFFSET
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3,2
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PROGRAM
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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, !isprime(n*(i-1)+j)); print1(permRWNb(a)", ")) - Herman Jamke (hermanjamke(AT)fastmail.fm), May 14 2007
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CROSSREFS
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Sequence in context: A004661 A074430 A064028 this_sequence A102744 A145951 A083215
Adjacent sequences: A110947 A110948 A110949 this_sequence A110951 A110952 A110953
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KEYWORD
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nonn
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AUTHOR
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Simone Severini (ss54(AT)york.ac.uk), Sep 25 2005
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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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