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A178297
Number of collinear point 6-tuples in a 7 X 7 X 7 X... n-dimensional cubic grid
0
0, 7, 116, 1459, 16520, 177727, 1861436, 19230379, 197501840
OFFSET
0,2
FORMULA
Conjecture: a(n) = 11^n/2+5*9^n/2-3*7^n. a(n)= 27*a(n-1) -239*a(n-2) +693*a(n-3). G.f.: x*(-7+73*x)/((11*x-1)*(7*x-1)*(9*x-1)). [R. J. Mathar May 24 2010]
CROSSREFS
Sequence in context: A063399 A220181 A328813 * A285394 A339390 A376042
KEYWORD
nonn
AUTHOR
R. H. Hardin, suggested by R. J. Mathar in the Sequence Fans Mailing List, May 24 2010
STATUS
approved