%I A134978
%S A134978 0,1,6,15,28,53,74,111,152,209,246,339,384,473,582,695,756,917,986,1175,
%T A134978 1340,1493,1578,1855,2008,2193,2398,2683,2792,3185,3302,3603,3880,4129,
%U A134978 4446,4943,5084,5365,5698,6231,6388,6973,7138,7615,8172,8517,8698,9431
%N A134978 Number of 2 X 2 singular integer matrices with entries from {2,...,n}.
%Y A134978 Cf. A134506.
%Y A134978 Sequence in context: A096892 A000384 A164000 this_sequence A115742 A026102 
               A144519
%Y A134978 Adjacent sequences: A134975 A134976 A134977 this_sequence A134979 A134980 
               A134981
%K A134978 nice,nonn
%O A134978 1,3
%A A134978 Graziano Aglietti (mg5055(AT)mclink.it), Feb 04 2008