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A017903
Expansion of 1/(1 - x^9 - x^10 - ...).
6
1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 15, 19, 24, 30, 37, 45, 54, 64, 76, 91, 110, 134, 164, 201, 246, 300, 364, 440, 531, 641, 775, 939, 1140, 1386, 1686, 2050, 2490, 3021, 3662, 4437, 5376, 6516, 7902, 9588
OFFSET
0,19
COMMENTS
A Lamé sequence of higher order.
a(n) = number of compositions of n in which each part is >=9. - Milan Janjic, Jun 28 2010
a(n+9) equals the number of n-length binary words such that 0 appears only in a run which length is a multiple of 9. - Milan Janjic, Feb 17 2015
LINKS
I. M. Gessel, Ji Li, Compositions and Fibonacci identities, J. Int. Seq. 16 (2013) 13.4.5
J. Hermes, Anzahl der Zerlegungen einer ganzen rationalen Zahl in Summanden, Math. Ann., 45 (1894), 371-380.
Augustine O. Munagi, Integer Compositions and Higher-Order Conjugation, J. Int. Seq., Vol. 21 (2018), Article 18.8.5.
FORMULA
G.f.: (x-1)/(x-1+x^9). - Alois P. Heinz, Aug 04 2008
For positive integers n and k such that k <= n <= 9*k, and 8 divides n-k, define c(n,k) = binomial(k,(n-k)/8), and c(n,k) = 0, otherwise. Then, for n>= 1, a(n+9) = sum(c(n,k), k=1..n). - Milan Janjic, Dec 09 2011
a(n) = A005711(n-10) for n > 9. - Alois P. Heinz, May 21 2018
MAPLE
f := proc(r) local t1, i; t1 := []; for i from 1 to r do t1 := [op(t1), 0]; od: for i from 1 to r+1 do t1 := [op(t1), 1]; od: for i from 2*r+2 to 50 do t1 := [op(t1), t1[i-1]+t1[i-1-r]]; od: t1; end; # set r = order
a:= n-> (Matrix(9, (i, j)-> if (i=j-1) then 1 elif j=1 then [1, 0$7, 1][i] else 0 fi)^n)[9, 9]: seq(a(n), n=0..55); # Alois P. Heinz, Aug 04 2008
MATHEMATICA
CoefficientList[(1-x)/(1-x-x^9) + O[x]^70, x] (* Jean-François Alcover, Jun 08 2015 *)
PROG
(PARI) Vec((x-1)/(x-1+x^9)+O(x^99)) \\ Charles R Greathouse IV, Sep 26 2012
CROSSREFS
For Lamé sequences of orders 1 through 9 see A000045, A000930, A017898-A017904.
Cf. A005711.
Sequence in context: A246084 A260768 A130224 * A005711 A322856 A280863
KEYWORD
nonn,easy
STATUS
approved