Problem
COM-B1-M12-P010 Set 3. Strings
#10
★★☆☆☆ Level 2 of 5
How many binary strings of length \(6\) contain no two adjacent ones?
Use \(a_n=a_{n-1}+a_{n-2}\).
With \(a_0=1\), \(a_1=2\), we get \(a_2=3\), \(a_3=5\), \(a_4=8\), \(a_5=13\), \(a_6=21\).
Recurrence by the last symbol.