A250701 - OEIS

%I #4 Nov 26 2014 22:05:21

%S 654,4958,30719,160486,735523,3020711,11354082,39603227,129764854,

%T 403049071,1195876182,3410274979,9395374116,25113321720,65362902075,

%U 166156830176,413619900804,1010542241094,2427848472870,5745600307078

%N Number of (n+1)X(2+1) 0..3 arrays with nondecreasing x(i,j)+x(i,j-1) in the i direction and nondecreasing min(x(i,j),x(i-1,j)) in the j direction

%C Column 2 of A250707

%H R. H. Hardin, <a href="/A250701/b250701.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 13*a(n-1) -64*a(n-2) +112*a(n-3) +193*a(n-4) -1145*a(n-5) +1171*a(n-6) +2815*a(n-7) -7600*a(n-8) +620*a(n-9) +17570*a(n-10) -16376*a(n-11) -18514*a(n-12) +37522*a(n-13) +1693*a(n-14) -44011*a(n-15) +19988*a(n-16) +29252*a(n-17) -26851*a(n-18) -9189*a(n-19) +18134*a(n-20) -1082*a(n-21) -7142*a(n-22) +2176*a(n-23) +1569*a(n-24) -849*a(n-25) -139*a(n-26) +153*a(n-27) -9*a(n-28) -11*a(n-29) +2*a(n-30)

%e Some solutions for n=4

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_, Nov 26 2014