alphanumeric characters vs alphanumerics

alphanumeric characters and alphanumerics both are nouns.

Word	Noun	Adjective	Verb	Adverb
alphanumeric characters	Yes	No	No	No
alphanumerics	Yes	No	No	No

As nouns, alphanumeric characters and alphanumerics are synonyms defined as:

alphanumeric characters and alphanumerics: a character set that includes letters and digits and punctuation

alphanumeric characters (noun)	alphanumerics (noun)
a character set that includes letters and digits and punctuation	a character set that includes letters and digits and punctuation