|
|
A178352
|
|
Number of collinear point triples in a 6 X 6 X 6 X ... n-dimensional cubic grid
|
|
1
|
|
|
|
OFFSET
|
0,2
|
|
LINKS
|
|
|
FORMULA
|
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]
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
R. H. Hardin, suggested by R. J. Mathar in the Sequence Fans Mailing List, May 25 2010
|
|
STATUS
|
approved
|
|
|
|