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%I #3 Mar 31 2012 12:35:45
%S 0,35,660,9767,135240,1856075,25897500,371453327,5493496080,
%T 83634563315
%N Number of collinear point 4-tuples in a 7 X 7 X 7 X ... n-dimensional cubic grid
%F Conjecture: a(n) = 3*13^n/2+3*11^n+9^(n+1)/2-19*7^n/2+17^n/2 ; a(n) = +57*a(n-1) -1270*a(n-2) +13830*a(n-3) -73609*a(n-4) +153153*a(n-5). G.f: x*(-35+1335*x-16597*x^2+67329*x^3) / ( (11*x-1)*(13*x-1)*(17*x-1)*(9*x-1)*(7*x-1) ). [R. J. Mathar May 25 2010]
%K nonn
%O 0,2
%A _R. H. Hardin_, suggested by R. J. Mathar in the Sequence Fans Mailing List, May 25 2010
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