%N Triangle read by rows where t(n,m) is the (ceiling(n/m))th integer from among those positive integers not occurring earlier in the sequence.
%C This is a self-inverse permutation of the positive integers. For fixed n, U(n,k) as defined above is a permution of 1..n. - _Franklin T. Adams-Watters_, Jul 25 2006
%F T(n,k) = n(n-1)/2 + U(n,k), where U(n,k) = ceiling(n/k) if ceiling(n/ceiling(n/k)) = k, otherwise U(n,k) = k. - _Franklin T. Adams-Watters_, Jul 25 2006
%Y Cf. A120911.
%A _Leroy Quet_, Jul 15 2006
%E More terms from _Franklin T. Adams-Watters_, Jul 25 2006