cp's OEIS Frontend

A239600 Number of 2Xn 0..3 arrays with no element equal to zero plus the sum of elements to its left or one plus the sum of the elements above it or one plus the sum of the elements diagonally to its northwest or one plus the sum of the elements antidiagonally to its northeast, modulo 4.

%I A239600 #6 Jun 02 2025 09:29:38
%S A239600 3,3,15,64,244,1030,4303,17923,75264,316087,1329006,5592784,23545716,
%T A239600 99155410,417639459,1759279887,7411361169,31223344768,131544340291,
%U A239600 554206795807,2334940230536,9837444241610,41446741048349,174622202605439
%N A239600 Number of 2Xn 0..3 arrays with no element equal to zero plus the sum of elements to its left or one plus the sum of the elements above it or one plus the sum of the elements diagonally to its northwest or one plus the sum of the elements antidiagonally to its northeast, modulo 4.
%C A239600 Row 2 of A239599
%H A239600 R. H. Hardin, <a href="/A239600/b239600.txt">Table of n, a(n) for n = 1..98</a>
%F A239600 Empirical: a(n) = 8*a(n-1) -20*a(n-2) +34*a(n-3) -111*a(n-4) +174*a(n-5) -122*a(n-6) +518*a(n-7) -341*a(n-8) -675*a(n-9) -1185*a(n-10) -967*a(n-11) +4025*a(n-12) +4959*a(n-13) +4034*a(n-14) -3986*a(n-15) -19979*a(n-16) -8427*a(n-17) -7967*a(n-18) +26414*a(n-19) +23797*a(n-20) +16119*a(n-21) +20898*a(n-22) -32421*a(n-23) -3129*a(n-24) -50644*a(n-25) -27518*a(n-26) +3200*a(n-27) -2410*a(n-28) +25372*a(n-29) +8923*a(n-30) +10252*a(n-31) +12108*a(n-32) +1635*a(n-33) -1564*a(n-34) +436*a(n-35) -2746*a(n-36) -436*a(n-37) +368*a(n-38) -998*a(n-39) -486*a(n-40) -227*a(n-41) -151*a(n-42) -21*a(n-43) -4*a(n-44) for n>47
%e A239600 Some solutions for n=4
%e A239600 ..3..0..0..2....3..0..0..0....3..0..0..2....2..3..3..2....2..3..3..2
%e A239600 ..3..2..2..0....2..3..3..2....2..3..2..2....2..1..1..2....2..1..2..2
%K A239600 nonn
%O A239600 1,1
%A A239600 _R. H. Hardin_, Mar 22 2014