OFFSET
8,2
REFERENCES
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 8..1000
D. R. Breach, Letter to N. J. A. Sloane, Jun 1980
Philippe Flajolet, Balls and Urns, etc., A problem in submarine detection (solution to problem 68-16).
M. Hayes (proposer) and D. R. Breach (solver), A combinatorial problem, Problem 68-16, SIAM Rev. 12 (1970), 294-297.
Index entries for linear recurrences with constant coefficients, signature (5,-10,10,-5,1).
FORMULA
G.f.: x^8*(1 + 3*x + x^2 - 11*x^5 + 7*x^6)/(1 - x)^5. - Vladeta Jovovic, Apr 13 2008
a(n) = (n^4 + 10*n^3 - 445*n^2 + 2690*n - 1656)/24 for n > 9. - Colin Barker, May 10 2012
MATHEMATICA
f[x_] := x^8*(1 + 3*x + x^2 - 11*x^5 + 7*x^6)/(1 - x)^5; Drop[ CoefficientList[ Series[f[x], {x, 0, 44}], x], 8] (* Jean-François Alcover, Oct 05 2011, after Vladeta Jovovic *)
LinearRecurrence[{5, -10, 10, -5, 1}, {1, 8, 31, 85, 190, 360, 610}, 40] (* Harvey P. Dale, Aug 26 2019 *)
PROG
(Magma) I:=[1, 8, 31, 85, 190, 360, 610]; [n le 7 select I[n] else 5*Self(n-1)-10*Self(n-2)+10*Self(n-3)-5*Self(n-4)+Self(n-5): n in [1..40]]; // Vincenzo Librandi, May 11 2012
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
EXTENSIONS
Corrected and extended by Vladeta Jovovic, Apr 13 2008
Name clarified by Alois P. Heinz, Oct 02 2017
STATUS
approved