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Squares of A002278.
9

%I #7 Nov 11 2019 09:22:43

%S 0,16,1936,197136,19749136,1975269136,197530469136,19753082469136,

%T 1975308602469136,197530863802469136,19753086415802469136,

%U 1975308641935802469136,197530864197135802469136

%N Squares of A002278.

%C A transformation of the Wonderful Demlo numbers (A002477).

%H Colin Barker, <a href="/A075413/b075413.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) = A002278(n)^2 = (4 * A002275(n) )^2 = 16 * (A002275(n) )^2.

%F From _Colin Barker_, Jul 17 2019: (Start)

%F G.f.: 16*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) = 16*(10^n-1)^2/81.

%F (End)

%e a(2) = 44^2 = 1936.

%o (PARI) concat(0, Vec(16*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