Removing rows from data

[MDX2013]

I have Column A (two empty rows between data), and I need to get to column B with a formula
[TABLE="width: 500"]
<tbody>[TR]
[TD]Column A[/TD]
[TD]Column B[/TD]
[/TR]
[TR]
[TD]a[/TD]
[TD]a[/TD]
[/TR]
[TR]
[TD][/TD]
[TD]a[/TD]
[/TR]
[TR]
[TD][/TD]
[TD]b[/TD]
[/TR]
[TR]
[TD]b[/TD]
[TD]b[/TD]
[/TR]
[TR]
[TD][/TD]
[TD]c[/TD]
[/TR]
[TR]
[TD][/TD]
[TD]c[/TD]
[/TR]
[TR]
[TD]c[/TD]
[TD][/TD]
[/TR]
</tbody>[/TABLE]

I am an excel novice trying to keep up! Any explination along with a solution would be greatly appreciated

 

[Rick Rothstein]

Give this formula a try...

=INDEX(A:A,3*ROUND(ROWS(B$1:B1)/2,0)-2)