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%I #9 Nov 11 2019 09:22:51
%S 0,25,3025,308025,30858025,3086358025,308641358025,30864191358025,
%T 3086419691358025,308641974691358025,30864197524691358025,
%U 3086419753024691358025,308641975308024691358025
%N Squares of A002279: a(n) = (5*(10^n - 1)/9)^2.
%C A transformation of the Wonderful Demlo numbers (A002477).
%H Colin Barker, <a href="/A075414/b075414.txt">Table of n, a(n) for n = 0..100</a>
%H G. Villemin, <a href="http://villemin.gerard.free.fr/Wwwgvmm/Addition/P100a500/Carrerep.htm">Variations sur les carrés</a>
%H <a href="/index/Rec#order_03">Index entries for linear recurrences with constant coefficients</a>, signature (111,-1110,1000).
%F a(n) = A002279(n)^2 = (5 * A002275(n) )^2 = 25 * (A002275(n) )^2.
%F From _Colin Barker_, Jul 17 2019: (Start)
%F G.f.: 25*x*(1 + 10*x) / ((1 - x)*(1 - 10*x)*(1 - 100*x)).
%F a(n) = 111*a(n-1) - 1110*a(n-2) + 1000*a(n-3) for n>2.
%F a(n) = 25*(10^n-1)^2/81.
%F (End)
%e a(2) = 55^2 = 3025.
%o (PARI) concat(0, Vec(25*x*(1 + 10*x) / ((1 - x)*(1 - 10*x)*(1 - 100*x)) + O(x^20))) \\ _Colin Barker_, Jul 17 2019
%Y Cf. A075411, A075412, A075413, A075414, A075415, A075416, A075417, A002283.
%K easy,nonn
%O 0,2
%A Michael Taylor (michael.taylor(AT)vf.vodafone.co.uk), Sep 14 2002
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