cp's OEIS Frontend

A231857 Number of 3Xn 0..2 arrays with no element having a strict majority of its horizontal and antidiagonal neighbors equal to itself plus one mod 3, with upper left element zero (rock paper and scissors drawn positions).

%I A231857 #6 Jun 02 2025 08:48:35
%S A231857 9,55,656,7339,85288,991167,11529929,134163686,1561220559,18167587282,
%T A231857 211412670503,2460168784055,28628514590530,333144562652494,
%U A231857 3876739724171184,45112880641621747,524969986286019848
%N A231857 Number of 3Xn 0..2 arrays with no element having a strict majority of its horizontal and antidiagonal neighbors equal to itself plus one mod 3, with upper left element zero (rock paper and scissors drawn positions).
%C A231857 Row 3 of A231855
%H A231857 R. H. Hardin, <a href="/A231857/b231857.txt">Table of n, a(n) for n = 1..210</a>
%F A231857 Empirical: a(n) = 15*a(n-1) -33*a(n-2) -96*a(n-3) +258*a(n-4) +412*a(n-5) -873*a(n-6) -1455*a(n-7) +1110*a(n-8) +4203*a(n-9) +2658*a(n-10) -10249*a(n-11) -12826*a(n-12) +15687*a(n-13) +27224*a(n-14) -12857*a(n-15) -37317*a(n-16) +9206*a(n-17) +17841*a(n-18) +107*a(n-19) +3350*a(n-20) -8989*a(n-21) +583*a(n-22) +8*a(n-23) +12093*a(n-24) -21445*a(n-25) +13211*a(n-26) -2506*a(n-27) +2401*a(n-28) -2357*a(n-29) +397*a(n-30) -8*a(n-31) +70*a(n-32) -32*a(n-33) -10*a(n-34) -4*a(n-35) for n>39
%e A231857 Some solutions for n=4
%e A231857 ..0..0..2..2....0..2..2..0....0..2..1..1....0..2..2..1....0..0..0..2
%e A231857 ..1..2..2..2....2..2..0..0....2..1..1..2....2..2..0..1....2..2..2..1
%e A231857 ..0..1..0..0....1..0..0..0....0..0..0..1....2..0..2..2....1..0..0..0
%K A231857 nonn
%O A231857 1,1
%A A231857 _R. H. Hardin_, Nov 14 2013