|
%I #4 Nov 03 2013 16:34:50
%S 0,0,42,438,4674,53530,616562,7084870,81402688,935286238,10746062272,
%T 123467810184,1418593781388,16299052416028,187269334301006,
%U 2151646785715718,24721526971823592,284040066485994938
%N Number of 4Xn 0..3 arrays x(i,j) with each element horizontally or antidiagonally next to at least one element with value (x(i,j)+1) mod 4, no adjacent elements equal, and upper left element zero
%C Row 4 of A231108
%H R. H. Hardin, <a href="/A231110/b231110.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 28*a(n-1) -284*a(n-2) +1189*a(n-3) -144*a(n-4) -16202*a(n-5) +43314*a(n-6) +51726*a(n-7) -378092*a(n-8) +142812*a(n-9) +1787045*a(n-10) -2071922*a(n-11) -5399600*a(n-12) +10035017*a(n-13) +9756451*a(n-14) -27257530*a(n-15) -9262577*a(n-16) +43800387*a(n-17) +823484*a(n-18) -25963993*a(n-19) -5631788*a(n-20) -43551782*a(n-21) +58894906*a(n-22) +72195172*a(n-23) -73850308*a(n-24) +9275284*a(n-25) -85663152*a(n-26) -50216070*a(n-27) +247099342*a(n-28) -15789086*a(n-29) -168327877*a(n-30) +34428902*a(n-31) -8906080*a(n-32) +16412437*a(n-33) +62237635*a(n-34) -31892052*a(n-35) -25353207*a(n-36) +10821699*a(n-37) -31603*a(n-38) +689681*a(n-39) +2169758*a(n-40) -686435*a(n-41) -375254*a(n-42) -46338*a(n-43) -50759*a(n-44) +32108*a(n-45) +27901*a(n-46) +299*a(n-47) -4056*a(n-48) -595*a(n-49) +162*a(n-50) +48*a(n-51) for n>56
%e Some solutions for n=4
%e ..0..1..2..1....0..1..2..3....0..1..0..1....0..1..2..1....0..1..2..1
%e ..0..3..2..3....0..1..0..3....2..3..2..1....2..3..0..3....0..3..2..1
%e ..2..1..0..3....0..3..0..1....2..3..0..3....2..3..2..3....0..1..3..2
%e ..0..1..2..1....2..3..2..1....2..1..0..3....2..1..0..3....3..0..1..0
%K nonn
%O 1,3
%A _R. H. Hardin_, Nov 03 2013
| 