%I
%S 1,3,2,6,5,4,10,8,9,7,15,13,12,14,11,21,18,17,19,20,16,28,25,24,23,26,
%T 27,22,36,32,31,30,33,34,35,29,45,41,39,40,38,42,43,44,37,55,50,49,48,
%U 47,51,52,53,54,46,66,61,59,58,60,57,62,63,64,65,56,78,72,70,69,71,68
%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 selfinverse permutation of the positive integers. For fixed n, U(n,k) as defined above is a permution of 1..n.  _Franklin T. AdamsWatters_, Jul 25 2006
%F T(n,k) = n(n1)/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. AdamsWatters_, Jul 25 2006
%Y Cf. A120911.
%K easy,nonn,tabl
%O 1,2
%A _Leroy Quet_, Jul 15 2006
%E More terms from _Franklin T. AdamsWatters_, Jul 25 2006
