M3TILE - LATGACH3
Tác giả: flashmt
Ngôn ngữ: Pascal
var n,i:longint;
f,s:array[0..30] of longint;
begin
f[0]:=1; f[2]:=3;
s[0]:=1; s[2]:=4;
for i:=4 to 30 do
if not odd(i) then
begin
f[i]:=f[i-2]*3+s[i-4]*2;
s[i]:=s[i-2]+f[i];
end;
while true do
begin
read(n);
if n=-1 then halt
else writeln(f[n]);
end;
end.