![worksheet function - Excel formula to test if 15 or 16 digit number is a valid credit card and return true / false (Luhn's algorithm) - Super User worksheet function - Excel formula to test if 15 or 16 digit number is a valid credit card and return true / false (Luhn's algorithm) - Super User](https://i.stack.imgur.com/8Szu8.png)
worksheet function - Excel formula to test if 15 or 16 digit number is a valid credit card and return true / false (Luhn's algorithm) - Super User
![worksheet function - Excel formula to test if 15 or 16 digit number is a valid credit card and return true / false (Luhn's algorithm) - Super User worksheet function - Excel formula to test if 15 or 16 digit number is a valid credit card and return true / false (Luhn's algorithm) - Super User](https://i.stack.imgur.com/n2btt.png)
worksheet function - Excel formula to test if 15 or 16 digit number is a valid credit card and return true / false (Luhn's algorithm) - Super User
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