I need a formula to help me find "True/False" results based on 2 columns.

1) First column has the Tag # (these can appear more than twice)
2) Second column has the price (these can be different, but the 1st price is always right)
3) 90% of time the tag #'s will have the same price, but there is occasions when the price is different for the same tag #.

In that case, I want to find the instances that are different using a formula that will give me a "TRUE" or "FALSE" result (or whatever works best)
My example below illustrates column A (tag #) and column B (price) and column C (what the formula should produce)
Please note that the price on the 1st one will always be right.


TAG # $-PRICE FORMULA

123456 $35 SHOULD BE TRUE
123456 $35 SHOULD BE TRUE
123456 $45 SHOULD BE FALSE
123456 $85 SHOULD BE FALSE