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%I #3 Mar 31 2012 12:35:45
%S 0,20,372,5696,85584,1324160,21306432,354876416,6065958144,
%T 105562511360
%N Number of collinear point triples in a 6 X 6 X 6 X ... n-dimensional cubic grid
%F Conjecture: a(n) = 2*8^n-9*6^n/2+12^n+18^n/2+10^n. a(n) = +54*a(n-1) -1124*a(n-2) +11304*a(n-3) -55008*a(n-4) +103680*a(n-5). G.f.: 4*x*(-5+177*x-2022*x^2+7488*x^3) / ( (12*x-1)*(6*x-1)*(8*x-1)*(18*x-1)*(10*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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