|
%I #3 Mar 25 2013 07:32:56
%S 27,729,1973,78213,1044311,22982345,502081983,9622736121,218268103915,
%T 6831466723781,157202982490683,3596007897529929
%N Number of 6Xn 0..1 arrays with all rows having a nonnegative second derivative, and all and columns having a positive second derivative in a quadratic least squares fit, with one and two element arrays taken as having a zero second derivative
%C Row 4 of A223652
%e Some solutions for n=3
%e ..1..1..1....1..1..1....1..0..1....1..0..1....1..1..1....1..1..1....0..0..1
%e ..0..0..1....1..0..0....0..0..0....1..1..1....1..0..0....0..0..0....0..0..1
%e ..1..0..0....1..0..0....1..0..0....0..0..1....1..0..1....0..0..0....0..0..0
%e ..0..0..1....1..0..0....1..0..1....1..0..0....1..1..1....0..0..1....1..0..1
%e ..0..0..1....0..0..0....1..0..0....1..0..0....0..0..1....1..0..0....0..0..0
%e ..1..0..1....1..0..0....1..1..1....1..1..1....1..1..1....1..0..1....1..1..1
%K nonn
%O 1,1
%A _R. H. Hardin_ Mar 25 2013
| 