A253527 - OEIS

%I #4 Jan 03 2015 09:07:10

%S 459,2722,9255,27070,71333,176266,416901,955594,2141571,4715371,

%T 10248721,22049172,47076283,99907559,211046947,444155161,931919916,

%U 1950390796,4073131178,8490131272,17667326091,36708441877,76165100413,157828885543

%N Number of (n+1)X(2+1) 0..2 arrays with every 2X2 subblock antidiagonal maximum minus diagonal minimum nondecreasing horizontally and diagonal maximum minus antidiagonal minimum nondecreasing vertically

%C Column 2 of A253533

%H R. H. Hardin, <a href="/A253527/b253527.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 7*a(n-1) -12*a(n-2) -24*a(n-3) +97*a(n-4) -31*a(n-5) -238*a(n-6) +262*a(n-7) +225*a(n-8) -495*a(n-9) +16*a(n-10) +428*a(n-11) -193*a(n-12) -161*a(n-13) +138*a(n-14) +6*a(n-15) -32*a(n-16) +8*a(n-17) for n>27

%e Some solutions for n=4

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_, Jan 03 2015