OFFSET
1,1
COMMENTS
Vertical cylinder: a chessboard where it is supposed that the columns 1 and 8 are in contact (number of columns = 8, number of rows = 2n).
LINKS
Ray Chandler, Table of n, a(n) for n = 1..3302
V. Kotesovec, Non-attacking chess pieces
Index entries for linear recurrences with constant coefficients, signature (7, -19, 25, -16, 4).
FORMULA
Recurrence: a(n) = 4*a(n-5) - 16*a(n-4) + 25*a(n-3) - 19*a(n-2) + 7*a(n-1).
G.f.: -(1 + 25*x + 51*x^2 + 11*x^3)/((x-1)^3*(2*x-1)^2).
a(n) = (221*n - 779)*2^n + 44*n^2 + 324*n + 780.
MATHEMATICA
LinearRecurrence[{7, -19, 25, -16, 4}, {32, 256, 1220, 4460, 13932}, 30] (* Harvey P. Dale, Jan 15 2016 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Vaclav Kotesovec, Sep 21 2011
STATUS
approved