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%I #6 Mar 31 2012 14:39:52
%S 15,21,51,99,249,309,339,441,615,1065,1071,1275,1311,1461,1665,1719,
%T 1935,2445,2451,2499,2511,2781,2829,2949,3015,3129,3435,3759,3789,
%U 3795,3819,3939,4161,4221,4761,4809,5709,5721,6291,6555,6699,6855,6921,7071
%N Composites for which the row of the prime-composite array (A063173) includes the leftmost element of both a zero-only antidiagonal and a zero-only diagonal(A067681).
%H N. Fernandez, <a href="http://www.borve.org/primeness/pcarray.html">The prime-composite array, B(m,n) and the Borve conjectures</a>
%e The 12th composite is 21. In the prime-composite array (A063173), all of the elements in the antidiagonal containing T(12,1) are 0 and so are all the elements of the diagonal containing T(12,1). So 21 is in the sequence.
%Y Cf. A063173, A063174, A063175, A067681.
%K nonn
%O 1,1
%A _Neil Fernandez_, Jul 09 2001
%E Edited and extended by _Robert G. Wilson v_, Feb 07 2002