%I A075312
%S A075312 2,15,28,60,104,135,198,240,322,416,476,589,714,792,936,1025,1188,1363,
%T A075312 1470,1664,1782,1995,2220,2356,2600,2856,3010,3285,3450,3744,4050,4233,
%U A075312 4558,4895,5096,5452,5664,6039,6426,6656,7062,7303,7728,8165,8424,8880
%N A075312 Pair the natural numbers (1,2),(3,5),(4,7),(6,10),(8,13),(9,15),(11,18),
               (12,20),(14,23),(16,26),... such that the k-th pair is (r,r+k) and 
               r is the smallest number not occurring earlier. This is the sequence 
               of the product of the members of a pair.
%Y A075312 The pairs are (A000211(n), A001950(n)). The sum is given by A003623.
%Y A075312 Sequence in context: A023651 A116028 A153080 this_sequence A128828 A032002 
               A071999
%Y A075312 Adjacent sequences: A075309 A075310 A075311 this_sequence A075313 A075314 
               A075315
%K A075312 nonn
%O A075312 1,1
%A A075312 Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Sep 13 2002