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%I #16 Sep 12 2015 11:00:23
%S 0,2,4374,259289,4255370,35093344,189681689,771464278,2559099153,
%T 7285273805,18416621598,42342480425,90097012004,179755977430,
%U 339666241815,612682858064,1061605357051,1776021648675,2880784715492
%N Number of ways to place 8 nonattacking wazirs on an 8 X n board.
%C Wazir is a (fairy chess) leaper [0,1].
%H Vincenzo Librandi, <a href="/A178410/b178410.txt">Table of n, a(n) for n = 1..1000</a>
%H V. Kotesovec, <a href="https://oeis.org/wiki/User:Vaclav_Kotesovec">Non-attacking chess pieces</a>, 6ed, 2013
%F a(n) = (1048576*n^8 -17432576*n^7 +136349696*n^6 -658958720*n^5 +2161896569*n^4 -4945969574*n^3 +7719028159*n^2 -7516702410*n +3494080800) / 2520, n >= 7.
%F G.f.: -x^2 * (8*x^13 -112*x^12 +870*x^11 -2812*x^10 +15019*x^9 +41114*x^8 +494109*x^7 +2357839*x^6 +5805509*x^5 +5762254*x^4 +2079065*x^3 +219995*x^2 +4356*x +2) / (x-1)^9.
%t CoefficientList[Series[- x (8 x^13 - 112 x^12 + 870 x^11 - 2812 x^10 + 15019 x^9 + 41114 x^8 + 494109 x^7 + 2357839 x^6 + 5805509 x^5 + 5762254 x^4 + 2079065 x^3 + 219995 x^2 + 4356 x + 2) / (x - 1)^9, {x, 0, 50}], x] (* _Vincenzo Librandi_, May 31 2013 *)
%Y Cf. A172229, A172230, A172231, A172232, A172234.
%K nonn,easy
%O 1,2
%A _Vaclav Kotesovec_, May 27 2010
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