cp's OEIS Frontend

Maple

q:= proc(a,b) local r,s,t,M,i;
   s:= floor((a-1)/8);
   if s <> (b-1) mod 8 then return 0 fi;
   s:= convert(s+8,base,2);
   r:= convert(8+floor((b-1)/8),base,2);
   t:= convert(8+ ((a-1) mod 8),base,2);
   M:= Vector(3);
   if s[1] = 1 and s[2] = 1 then M[1]:= 1; M[2]:= 1 fi;
   if s[2]=1 and s[3]=1 then M[2]:= M[2]+1; M[3]:= 1 fi;
   for i from 1 to 3 do if s[i]=1 then
     M[i]:= M[i]+r[i]+t[i];
     if M[i] = 0 or M[i]>2 then return 0 fi;
   fi od;
   1
end proc:
T:= Matrix(64,64, q);
u:= Vector[row](64):
v:= Vector(64):
for i from 0 to 7 do u[8*i+1]:= 1; v[i+1]:= 1;
od:
seq(u . T^n . v, n = 1 .. 100); # Robert Israel, Nov 12 2017