login
A017908
Expansion of 1/(1 - x^14 - x^15 - ...).
3
1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 17, 20, 24, 29, 35, 42, 50, 59, 69, 80, 92, 105, 119, 134, 151, 171, 195, 224, 259, 301, 351, 410, 479, 559, 651, 756, 875, 1009
OFFSET
0,29
COMMENTS
a(n) = number of compositions of n in which each part is >=14. - Milan Janjic, Jun 28 2010
a(n+27) equals the number of binary words of length n having at least 13 zeros between every two successive ones. - Milan Janjic, Feb 09 2015
LINKS
Index entries for linear recurrences with constant coefficients, signature (1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1).
FORMULA
G.f.: (x-1)/(x-1+x^14). - Alois P. Heinz, Aug 04 2008
For positive integers n and k such that k <= n <= 14*k, and 13 divides n-k, define c(n,k) = binomial(k,(n-k)/13), and c(n,k) = 0, otherwise. Then, for n>=1, a(n+14) = sum(c(n,k), k=1..n). - Milan Janjic, Dec 09 2011
MAPLE
a:= n-> (Matrix(14, (i, j)-> if (i=j-1) then 1 elif j=1 then [1, 0$12, 1][i] else 0 fi)^n)[14, 14]: seq(a(n), n=0..62); # Alois P. Heinz, Aug 04 2008
MATHEMATICA
LinearRecurrence[{1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1}, {1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}, 80] (* Vladimir Joseph Stephan Orlovsky, Feb 17 2012 *)
PROG
(PARI) Vec((x-1)/(x-1+x^14)+O(x^99)) \\ Charles R Greathouse IV, Sep 26 2012
CROSSREFS
Sequence in context: A033067 A032512 A050723 * A044965 A044827 A048313
KEYWORD
nonn,easy
STATUS
approved