After reading into this puzzle post ..I have a question maybe someone can answer
1 5HpHagT65TZzG1PH3CSu63k8DbpvD8s5ip4nEB3kEsreAnchuDf
2 5HpHagT65TZzG1PH3CSu63k8DbpvD8s5ip4nEB3kEsreAvUcVfH
...
F 5HpHagT65TZzG1PH3CSu63k8DbpvD8s5ip4nEB3kEsreCMUnXUo
These are all valid private keys.... Just how many "NON valid" keys are in between each of the first 16 valid keys
and is there a pattern..

What you posted weren't the actual raw private keys but the base58 encoded and WIF formatted version of the private keys with the information stating it's uncompressed.
The hex representation of a base58 encoded and WIF formatted uncompressed key is:
80 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX YYYYYYYY
The hex representation of a base58 encoded and WIF formatted compressed key is:
80 XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX 01 YYYYYYYY
where XX is the raw private key and YY the checksum.
Your question regarding "how many invalid keys are in between" is ambiguous. You might also consider to open a new thread to reach appropriate audience.