%I
%S 2,4,5,7,8,9,11,12,13,15,16,17,18,19,21,22,23,24,25,27,28,29,30,31,32,
%T 34,35,36,37,38,39,40,42,43,44,45,46,47,48,50,51,52,53,54,55,56,57,58,
%U 60,61,62,63,64,65,66,67,68,70,71,72,73,74,75,76,77,78,79,81,82,83,84,85,86,87,88,89,90,91,93,94
%N a(n) = n + floor(sqrt(5*n/2)); complement of A183863.
%C Also n + floor(sqrt(5*n/2 + 1/2)) since 5*n/2 + 1/2 is never a square.  _Charles R Greathouse IV_, Feb 11 2011
%t a=5/2; b=1/2;
%t Table[n+Floor[(a*n+b)^(1/2)],{n,80}]
%t Table[n1+Ceiling[(n*nb)/a],{n,70}]
%o (PARI) a(n)=n+sqrtint(5*n/2)
%Y Cf. A183863.
%K nonn,easy
%O 1,1
%A _Clark Kimberling_, Jan 07 2011
