%I A077553
%S A077553 4,4,6,4,6,9,4,6,9,10,4,6,9,10,15,4,6,9,10,15,25,4,6,9,10,14,15,21,4,6,
%T A077553 9,10,14,15,21,25,4,6,9,10,14,15,21,25,35,4,6,9,10,14,15,21,25,35,49,4,
%U A077553 6,9,10,14,15,21,22,25,33,35,4,6,9,10,14,15,21,22,25,33,35,49,4,6,9,10
%N A077553 Triangle in which the n-th row contains n distinct composite numbers 
               with the least product and has least number of prime divisors. No 
               member of a row is a multiple of another member of the row.
%C A077553 If there are two sets of distinct composite numbers satisfying the above 
               condition then the set with lesser product is chosen irrespective 
               of the number of prime divisors. Perhaps the ambiguity may not arise. 
               E.g. Row 6 is 4,6,9,10,15,25. This row can not be extended to get 
               the next row without bringing in another prime because every number 
               divisible by 2,3 or 5 will be a multiple of one of the previous terms. 
               Hence in row 7, prime 7 has to be brought in and then we get a new 
               set of numbers 4,6,9,10,14,15,21.
%H A077553 Tanya Khovanova, <a href="http://www.tanyakhovanova.com/RecursiveSequences/
               RecursiveSequences.html">Recursive Sequences</a>
%e A077553 4;
%e A077553 4,6;
%e A077553 4,6,9;
%e A077553 4,6,9,10;
%e A077553 4,6,9,10,15;
%e A077553 4,6,9,10,15,25;
%e A077553 4,6,9,10,14,15,21;
%Y A077553 Cf. A001358, A077554, A077555, A087112, A005843.
%Y A077553 Sequence in context: A021228 A059656 A064041 this_sequence A010659 A131089 
               A066560
%Y A077553 Adjacent sequences: A077550 A077551 A077552 this_sequence A077554 A077555 
               A077556
%K A077553 nonn,tabl
%O A077553 0,1
%A A077553 Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Nov 10 2002
%E A077553 More terms from Ray Chandler (rayjchandler(AT)sbcglobal.net), Aug 21 
               2003