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%I #13 Jan 24 2022 04:10:28
%S 0,0,1,1,4,5,10,18,35,65,120,225,430,814,1549,2981,5739,11084,21474,
%T 41663,81033,157830,307912,601482,1176314,2302911,4513106,8851907,
%U 17376317,34134944,67101922,131990741,259779732,511566355,1007901666
%N Number of positive integers <= 2^n of form 4 x^2 + 9 y^2.
%H <a href="/index/Qua#quadpop">Index entries for sequences related to populations of quadratic forms</a>
%Y Cf. A020684.
%K nonn
%O 0,5
%A _David W. Wilson_