0 or 1 combinations such that we do not have two 1's immediately in sequence
<p>My requirement is for a code to find the number of combinations of two digits only 0 and 1 for X digit size which may vary from 1 .. 1000 such that no time two 1 can be immediately in sequence but 0's are possible</p>

<p>Say for input of 4 digit we have</p>

<pre><code>1010 1000 0000 0101 0001 0010 0100 1001 
</code></pre>

<p>I am not sure which of algos to generate such a combinations of 0's and 1's?</p>
