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%I #13 Aug 28 2022 04:23:17
%S 1,54,1701,40824,826686,14880348,245525742,3788111448,55401129927,
%T 775615818978,10470813556203,137072468372112,1747673971744428,
%U 21778706417122872,266011342666286508,3192136111995438096,37707107822946112509,439176902879019428046
%N a(n) = binomial(n + 5, 5)*9^n.
%C Number of n-permutations (n>=5) of 10 objects p, r, q, u, v, w, z, x, y, z with repetition allowed, containing exactly five (5) u's.
%H Vincenzo Librandi, <a href="/A173188/b173188.txt">Table of n, a(n) for n = 0..400</a>
%H <a href="/index/Rec#order_06">Index entries for linear recurrences with constant coefficients</a>, signature (54,-1215,14580,-98415,354294,-531441).
%F a(n) = C(n + 5, 5)*9^n.
%F From _Amiram Eldar_, Aug 28 2022: (Start)
%F Sum_{n>=0} 1/a(n) = 184320*log(9/8) - 86835/4.
%F Sum_{n>=0} (-1)^n/a(n) = 450000*log(10/9) - 189645/4. (End)
%t Table[Binomial[n + 5, 5]*9^n, {n, 0, 20}]
%o (Magma) [Binomial(n+5, 5)*9^n: n in [0..20]]; // _Vincenzo Librandi_, Oct 13 2011
%Y Cf. A081139, A173000, A173187.
%K nonn,easy
%O 0,2
%A _Zerinvary Lajos_, Feb 12 2010