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%I #29 Jul 20 2014 09:47:49
%S 2,42,505,5586,59308,616995,6347878,64875490,660104281,6695709182,
%T 67762820595,684596704482,6907026402474,69611115440126,
%U 700946070114283,7053023642205904
%N Number of positive integers below 10^n requiring 3 positive squares in their representation as sum of squares.
%H Eric W. Weisstein, <a href="http://mathworld.wolfram.com/LagrangesFour-SquareTheorem.html">MathWorld -- Lagrange's Four-Square Theorem.</a>
%H Eric W. Weisstein, <a href="http://mathworld.wolfram.com/SumofSquaresFunction.html">MathWorld -- Sum of Squares Function.</a>
%F a(n) = #{k: A000419(k) < 10^n}.
%F A049416(n) + A180416(n) + a(n) + A167615(n) = A002283(n).
%Y Cf. A000419, A049416, A180416, A167615, A002283.
%K nonn,more
%O 1,1
%A _Martin Renner_, Jan 19 2011
%E a(6)=616995 by _Lars Blomberg_, May 03 2011
%E a(7)-a(10) from _Donovan Johnson_, Jul 01 2011
%E a(10) corrected and a(11)-a(16) from _Hiroaki Yamanouchi_, Jul 13 2014
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