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%I #15 Jun 13 2015 00:55:04
%S 1,0,0,1,0,1,1,0,2,2,1,3,3,3,6,5,6,11,10,13,19,19,27,35,37,52,65,74,
%T 100,121,145,192,230,282,365,440,548,695,843,1058,1327,1621,2035,2535,
%U 3119,3910,4851,5997,7503,9297,11528,14389,17829,22150,27596,34208,42536,52928,65655,81660,101525,126020,156738,194776,241888
%N Number of compositions of n into parts 3, 5 and 9.
%H <a href="/index/Rec#order_09">Index entries for linear recurrences with constant coefficients</a>, signature (0,0,1,0,1,0,0,0,1).
%F G.f.: 1/(1-x^3-x^5-x^9).
%F a(n) = a(n-3) + a(n-5) + a(n-9).
%e a(28)=100 The compositions of n into parts 3,5 and 9 are the permutations of (9955)(these are 4!/2!2!=6), (555553) (these are 6!/5!=6), (955333) (these are 6!/3!2!=60), (55333333) (these are 8!/6!2!=28).
%o (PARI) Vec( 1/(1-x^3-x^5-x^9) +O(x^66) ) \\ _Joerg Arndt_, Aug 24 2014
%Y Cf. A079957, A245367, A245369.
%K nonn,easy
%O 0,9
%A _David Neil McGrath_, Aug 24 2014
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