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%I #13 Aug 29 2022 04:41:06
%S 1,63,2205,56595,1188495,21630609,353299947,5299499205,74192988870,
%T 980996186170,12360551945742,149450309889426,1743586948709970,
%U 19715944727720430,216875392004924730,2327795874186192102,24441856678955017071,251607348165713411025
%N a(n) = binomial(n + 8, 8)*7^n .
%C With a different offset, number of n-permutations of 8 objects: r, s, t, u, v, z, x, y with repetition allowed, containing exactly eight, (8) u's.
%H Vincenzo Librandi, <a href="/A170932/b170932.txt">Table of n, a(n) for n = 0..300</a>
%H <a href="/index/Rec#order_09">Index entries for linear recurrences with constant coefficients</a>, signature (63,-1764,28812,-302526,2117682,-9882516,29647548,-51883209,40353607).
%F a(n) = C(n + 8, 8)*7^n.
%F From _Amiram Eldar_, Aug 29 2022: (Start)
%F Sum_{n>=0} 1/a(n) = 12082656/5 - 15676416*log(7/6).
%F Sum_{n>=0} (-1)^n/a(n) = 117440512*log(8/7) - 235229912/15. (End)
%t Table[Binomial[n + 8, 8]*7^n, {n, 0, 20}]
%o (Magma) [Binomial(n + 8, 8)*7^n: n in [0..20]]; // _Vincenzo Librandi_, Oct 12 2011
%Y Cf. A027474, A140107, A139641, A140404, A036226, A050989.
%K nonn,easy
%O 0,2
%A _Zerinvary Lajos_, Feb 08 2010
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