%I
%S 1,4,7,11,16,21,26,32,38,45,52,59,66,74,82,91,99,108,117,126,136,146,
%T 156,166,177,187,198,210,221,232,244,256,268,280,293,305,318,331,344,
%U 358,371,385,399,413,427,441,456,470,485,500
%N Let R(i,j) be the rectangle with antidiagonals 1; 2,3; 4,5,6; ...; n^3 is in antidiagonal a(n).
%F Round(n*(sqrt(2*n))).  _Vladeta Jovovic_, Jun 14 2003
%t Table[Round[n Sqrt[2n]],{n,50}] (* _Harvey P. Dale_, Feb 10 2020 *)
%Y Cf. A057045, A057062, A057048, A022846, A057057.
%K nonn
%O 1,2
%A _Clark Kimberling_, Jul 30 2000
