Camel Case - digits allowed - Upto 3 upper case letters

To be proper camel case a word with digits allowed and upto 3 upper case letters, a word:

• MUST start with a lower case alphabet (a through z)
• MUST have no spaces, punctuation or special characters
• CAN have at most 3 uppercase alphabets in a row
• CAN end in an uppercase alphabet

Notable examples

• camel01CC01 is valid lower camel case, with digits allowed , with upto 3 upper case letters