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A110950 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. 0
1, 3, 12, 36, 383, 1560, 19162, 97680, 1804643, 4082400, 207316912, 1186043040, 25595629200, 266545072080, 6282386337194, 26013379392000, 1682187039875545, 11884755543091200, 396276417247253760, 5491416186030297600 (list; graph; refs; listen; history; text; internal format)
OFFSET

3,2

LINKS

Table of n, a(n) for n=3..22.

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, !isprime(n*(i-1)+j)); print1(permRWNb(a)", ")) - Herman Jamke (hermanjamke(AT)fastmail.fm), May 14 2007

CROSSREFS

Sequence in context: A074430 A064028 A326241 * A102744 A145951 A083215

Adjacent sequences:  A110947 A110948 A110949 * A110951 A110952 A110953

KEYWORD

nonn

AUTHOR

Simone Severini, Sep 25 2005

EXTENSIONS

More terms from Herman Jamke (hermanjamke(AT)fastmail.fm), May 14 2007

STATUS

approved

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Last modified August 8 11:12 EDT 2020. Contains 336293 sequences. (Running on oeis4.)