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Expansion of 1/((1+x)(1-x)^9).
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%I #32 Jan 18 2024 09:48:12

%S 1,8,37,128,367,920,2083,4352,8518,15792,27966,47616,78354,125136,

%T 194634,295680,439791,641784,920491,1299584,1808521,2483624,3369301,

%U 4519424,5998876,7885280,10270924,13264896

%N Expansion of 1/((1+x)(1-x)^9).

%H Vincenzo Librandi, <a href="/A001780/b001780.txt">Table of n, a(n) for n = 0..2000</a>

%H Jia Huang, <a href="https://cs.uwaterloo.ca/journals/JIS/VOL26/Huang/huang8.html">Partially Palindromic Compositions</a>, J. Int. Seq. (2023) Vol. 26, Art. 23.4.1. See pp. 4, 17.

%H <a href="/index/Rec#order_10">Index entries for linear recurrences with constant coefficients</a>, signature (8,-27,48,-42,0,42,-48,27,-8,1).

%F a(n) = 431*n/168 + (-1)^n/512 + 391*n^3/288 + 26011*n^2/10080 + 797*n^4/1920 + 11*n^5/144 + n^6/120 + n^7/2016 + n^8/80640 + 511/512. - R. J. Mathar, Mar 15 2011

%F Boas-Buck recurrence: a(n) = (1/n)*Sum_{p=0..n-1} (9 + (-1)^(n-p))*a(p), n >= 1, a(0) = 1. See the Boas-Buck comment in A046521 (here for the unsigned column k = 4 with offset 0). - _Wolfdieter Lang_, Aug 10 2017

%F a(n)+a(n+1) = A000581(n+9) . - _R. J. Mathar_, Jan 06 2021

%o (PARI) Vec(1/(1+x)/(1-x)^9+O(x^99)) \\ _Charles R Greathouse IV_, Apr 18 2012

%Y Cf. A001769, A158454 (signed column k=4), A001779 (first differences), A169796 (binomial trans.).

%K nonn,easy

%O 0,2

%A _N. J. A. Sloane_