%I A064766
%S A064766 1,2,2,6,5,1,8,1,10,20,10,22,7,21,36,16,33,6,25,45,11,33,56,14,39,65,
%T A064766 14,42,71,10,41,73,1,35,70,106,23,61,100,4,45,87,130,21,66,112,159,36,
%U A064766 85,135,186,48,101,155,210,56,113,171,230,59,120,182,245,56,121,187
%N A064766 Fill a triangular array by rows by writing numbers 1, then 1 up to 2*3/
               2, then 1 up to 3*4/2, then 1 up to 4*5/2 and so on from 1 up to 
               the n-th triangular number. The final elements of the rows form the 
               sequence.
%e A064766 The array begins
%e A064766 ....1
%e A064766 ...1.2
%e A064766 ..3.1.2
%e A064766 .2.4.5.6
%e A064766 1.2.3.4.5
%Y A064766 Cf. A064865.
%Y A064766 Sequence in context: A062293 A054516 A062400 this_sequence A121178 A019749 
               A122070
%Y A064766 Adjacent sequences: A064763 A064764 A064765 this_sequence A064767 A064768 
               A064769
%K A064766 easy,nonn
%O A064766 0,2
%A A064766 Floor van Lamoen (fvlamoen(AT)hotmail.com), Oct 18 2001