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%I #21 Feb 12 2021 06:04:32
%S 0,144,207936,299843856,432374632704,623483920515600,
%T 899063381008862784,1296448771930859619216,1869478230060918562046976,
%U 2695786311299072635612120464,3887321991415032679634115662400
%N Squares that remain square when the digit 4 is appended.
%C The terms of the sequence are the squares of the y-values in the solution to the Pellian equation x^2-10*y^2=4. - _Colin Barker_, Sep 28 2013
%F Empirical g.f.: -144*x^2*(x+1) / ((x-1)*(x^2-1442*x+1)). - _Colin Barker_, Jan 31 2013
%F a(n) = 4*A023111(n). - _Colin Barker_, Sep 28 2013
%K nonn,base
%O 1,2
%A _David W. Wilson_
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