A253402 - OEIS

%I #4 Dec 31 2014 09:53:44

%S 2890,8168,27362,108950,367348,1489310,5662124,19137326,76649188,

%T 290244550,999559200,3957740954,14871518668,52003849470,204576756391,

%U 762458041400,2701018996090,10554526115684,39120811735708

%N Number of (n+1)X(3+1) 0..2 arrays with every 2X2 subblock diagonal maximum plus antidiagonal minimum unequal to its neighbors horizontally, vertically and ne+sw antidiagonally

%C Column 3 of A253407

%H R. H. Hardin, <a href="/A253402/b253402.txt">Table of n, a(n) for n = 1..210</a>

%F Empirical: a(n) = 110*a(n-3) +36*a(n-5) -3991*a(n-6) -585*a(n-8) +52096*a(n-9) +2025*a(n-10) -91236*a(n-11) -148031*a(n-12) -109980*a(n-13) +3055131*a(n-14) -1480502*a(n-15) +2990592*a(n-16) -36511806*a(n-17) -2686786*a(n-18) -39911958*a(n-19) +147090696*a(n-20) +29595122*a(n-21) +200744568*a(n-22) +113270946*a(n-23) +1094938904*a(n-24) +1034944920*a(n-25) +1165329114*a(n-26) -2355555162*a(n-27) -15406809552*a(n-28) -26810193924*a(n-29) -52241564502*a(n-30) +37661994702*a(n-31) -22411093566*a(n-32) -138593844558*a(n-33) +367423506531*a(n-34) +536621041170*a(n-35) -492681264867*a(n-36) -820603514628*a(n-37) +285322280544*a(n-38) -1356465015720*a(n-39) -3849251892984*a(n-40) -1508589297000*a(n-41) -265315644360*a(n-42) -2981331210528*a(n-43) -1326237776496*a(n-44) +2531891094912*a(n-45) +1666998108144*a(n-46) +241114900608*a(n-47) +2460625647696*a(n-48) +2785459772736*a(n-49) +248296560192*a(n-50) +537352144128*a(n-51) +856233711360*a(n-52) -62060691456*a(n-53) -74017317888*a(n-54) +1451188224*a(n-55) +1572120576*a(n-56) for n>63

%e Some solutions for n=4

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

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

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

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

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

%K nonn

%O 1,1

%A _R. H. Hardin_, Dec 31 2014