Not getting Combin Function

It's a statistical function.  What you input would be read by mathematician as "64 choose 2", or how many unique ways are there to choose 2 items from a list of 64, where the order doesn't matter, so AB and BA are the same thing.

A simple example is 5 choose 2, which the answer is 10.  Let's just do letters:

AB, AC, AD, AE, BC, BD, BE, CD, CE, DE

A with 4 possible second letters, B with 3 remaining second letters, then C with 2 more, D with only one possibility that wasn't earlier in the results.

There's a fun statistical calculation for determining the value that involves factorials, but you don't have to do that because Appian does it for you.  If you care about the order, like if you're trying to find the total number of possible combinations to a safe, that's actually called a "permutation".  Appian has a function for that too.

It's a statistical function.  What you input would be read by mathematician as "64 choose 2", or how many unique ways are there to choose 2 items from a list of 64, where the order doesn't matter, so AB and BA are the same thing.

A simple example is 5 choose 2, which the answer is 10.  Let's just do letters:

AB, AC, AD, AE, BC, BD, BE, CD, CE, DE

A with 4 possible second letters, B with 3 remaining second letters, then C with 2 more, D with only one possibility that wasn't earlier in the results.

There's a fun statistical calculation for determining the value that involves factorials, but you don't have to do that because Appian does it for you.  If you care about the order, like if you're trying to find the total number of possible combinations to a safe, that's actually called a "permutation".  Appian has a function for that too.