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%I #12 Sep 28 2023 10:16:16
%S 0,1,2,5,6,10,11,16,19,23,24,33,34,38,42,50,51,60,61,70,74,78,79,94,
%T 97,101,106,115,116,129,130,141,145,149,153,172,173,177,181,196,197,
%U 210,211,220,229,233,234,257,260,269,273,282,283,298,302,317,321,325,326,353,354,358,367,382,386,399,400,409,413,426
%N Sum_{k=2..n} floor(n/k)*floor((tau(k)+1)/2), where tau = A000005.
%C Number of quadratic polynomials with coefficients from {1..n} for which both roots are integers.
%C A generalization of A006318.
%H Dorin Andrica and Eugen J. Ionascu, <a href="http://www.emis.de/journals/ASUO/mathematics_/vol22-1/Andrica_D__Ionascu_E.J._nou-1__final_.pdf">On the number of polynomials with coefficients in [n]</a>, An. St. Univ. Ovidius Constanta, Vol. 22(1),2014, 13-23.
%Y Cf. A000005, A006318, A238097, A238098.
%K nonn
%O 1,3
%A _N. J. A. Sloane_, Feb 22 2014
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