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%I #13 Oct 03 2016 14:32:26
%S 23,567,6814,47358,239511,954226,3207212,9414828,24862239,60136329,
%T 135311658,286229762,574460495,1101240084,2028333848,3605765688,
%U 6211552455,10402472811,16984387958,27099325638,42342870823,64905898662,97761436356,144885584740,211543443215
%N Number of inequivalent (mod D_4) ways five checkers can be placed on an n X n board.
%H Heinrich Ludwig, <a href="/A242358/b242358.txt">Table of n, a(n) for n = 3..1000</a>
%H <a href="/index/Rec#order_17">Index entries for linear recurrences with constant coefficients</a>, signature (5,-4,-20,40,16,-100,44,110,-110,-44,100,-16,-40,20,4,-5,1).
%F a(n) = (n^10 - 10*n^8 + 35*n^6 + 52*n^5 - 210*n^4 + 140*n^3 - 56*n^2 + 48*n + IF(MOD(n, 2) = 1)*(52*n^5 - 145*n^4 + 140*n^3 - 80*n^2 + 48*n - 15))/960.
%F G.f.: x^3*(-23 - 452*x - 4071*x^2 - 16016*x^3 - 40397*x^4 - 59335*x^5 - 61954*x^6 - 38236*x^7 - 17221*x^8 - 3614*x^9 - 623*x^10 + 20*x^11 + x^12 + x^13)/((x-1)^11*(x+1)^6). - _Vaclav Kotesovec_, May 11 2014
%F a(n) = A054772(n, 5), n >=3. - _Wolfdieter Lang_, Oct 03 2016
%t Drop[CoefficientList[Series[x^3*(-23 - 452*x - 4071*x^2 - 16016*x^3 - 40397*x^4 - 59335*x^5 - 61954*x^6 - 38236*x^7 - 17221*x^8 - 3614*x^9 - 623*x^10 + 20*x^11 + x^12 + x^13)/((x-1)^11*(x+1)^6), {x, 0, 20}], x],3] (* _Vaclav Kotesovec_, May 11 2014 *)
%Y Cf. A054252, A008805, A014409, A082966, A242279, A054772.
%K nonn,easy
%O 3,1
%A _Heinrich Ludwig_, May 11 2014
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