A223493 - OEIS

A223493

Number of (n+2)X2 0..3 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

%I #4 Mar 20 2013 15:59:35

%S 784,11236,217156,3880900,62473216,1017418609,16958290176,

%T 258624119601,4292106627600,69919047021121,1108508414832900,

%U 17553241318913316,287190892511175249,4569212447729997376,73203072358679636409

%N Number of (n+2)X2 0..3 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 Column 2 of A223495

%H R. H. Hardin, <a href="/A223493/b223493.txt">Table of n, a(n) for n = 1..30</a>

%e Some solutions for n=1

%e ..1..3....2..0....2..2....2..0....0..1....3..1....3..3....1..3....2..1....1..0

%e ..0..2....0..0....2..0....2..0....0..0....0..1....2..2....0..1....1..1....1..0

%e ..0..2....0..2....3..2....3..1....3..1....2..2....2..3....3..2....3..3....3..3

%K nonn

%O 1,1

%A _R. H. Hardin_ Mar 20 2013