OFFSET
0,6
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 0..1000
V. Kotesovec, Ways of placing non-attacking queens and kings..., part of "Between chessboard and computer", 1996, pp. 204 - 206.
Index entries for linear recurrences with constant coefficients, signature (6,-15,20,-15,6,-1).
FORMULA
G.f.: 2*x^5*(4*x^11 - 11*x^10 + 16*x^9 + 7*x^8 - 32*x^7 + 38*x^6 + 6*x^5 + 8*x^4 - 8*x^3 + 37*x^2 - 10*x + 5)/(x - 1)^6.
Recurrence: a(n) = 6*a(n - 1) - 15*a(n - 2) + 20*a(n - 3) - 15*a(n - 4) + 6*a(n - 5) - a(n - 6), n >= 17.
Explicit formula (V. Kotesovec, 1992): a(n) = n^5 - 30*n^4 + 407*n^3 - 3098*n^2 + 13104*n - 24332, n >= 11.
MATHEMATICA
CoefficientList[Series[2 x^5 (4 x^11 -11 x^10 + 16 x^9 + 7 x^8 - 32 x^7 + 38 x^6 + 6 x^5 + 8 x^4 - 8 x^3 + 37 x^2 - 10 x + 5) / (x-1)^6, {x, 0, 30}], x] (* Vincenzo Librandi, May 12 2013 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Antonio G. Astudillo (afg_astudillo(AT)hotmail.com), May 31 2001
STATUS
approved