cp's OEIS Frontend

Maple

Configs:= map(t -> convert(t+3^6, base, 3)[1..6],[$0..3^6-1]):
q:= proc(a,b) local A,B;
   A:= Configs[a]; B:= Configs[b];
   if A[4..6]<> B[1..3] then return 0 fi;
   if A[4] <> A[1]+A[5]+B[4] mod 3  and A[4] <> A[2]+B[5] mod 3 then return 0 fi;
   if A[5] <> A[2]+A[4]+A[6]+B[5] mod 3 and A[5] <> A[1]+A[3]+B[4]+B[6] mod 3 then return 0 fi;
   if A[6] <> A[3]+A[5]+B[6] mod 3 and A[6] <> A[2]+B[5] mod 3 then return 0 fi;
   1
end proc:
T:= Matrix(3^6,3^6, q):
u:= Vector[row](3^6,proc(a) if Configs[a][1..3]=[0,0,0] then 1 else 0 fi end proc):
v:= Vector(3^6,proc(a) if Configs[a][4..6]=[0,0,0] then 1 else 0 fi end proc):
V[0]:= v:
for nn from 1 to 30 do V[nn]:= T . V[nn-1] od:
seq(u . V[n],n=1..30); # Robert Israel, Nov 17 2019