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A069740 Let M_n be the n X n matrix M_(i,j)=1/(i+j+ij); a(n) is the numerator of det(M_n). 0

%I

%S 1,1,1,1,4,1,64,4,65536,512,33554432,65536,68719476736,6442450944,

%T 9007199254740992,281474976710656,220326730624766167090200576,

%U 340010386766614455386112,486777830487640090174734030864384

%N Let M_n be the n X n matrix M_(i,j)=1/(i+j+ij); a(n) is the numerator of det(M_n).

%C Is a(n) always of the form 2^u*3^v?

%o (PARI) for(n=1,70,print1(numerator(matdet(matrix(n,n,i,j,1/(i*j+i+j)))),","))

%K easy,nonn

%O 1,5

%A _Benoit Cloitre_, Apr 21 2002

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Last modified October 3 11:41 EDT 2022. Contains 357231 sequences. (Running on oeis4.)