COUNTIF
 

Hi,

How am I able to "detect" the highest freq of a pair of number appears in a
string of numbers.

Example if there are 2 group of 6 numbers (1,2,3,4,5,6) & (1,3,5,7,9). Pair
(1,3) & Pair (3,5) & Pair (1,5) appears twice. How am I able to let excel do
the counting?

I tried using COUNTIF but COUNTIF only allow me to enter one criteria and
not 2 or more.