Pythagorein or Pythagorean: How To spell?

The word Pythagorein is misspelled against Pythagorean, a noun meaning "A follower of Pythagoras; one of the school of philosophers founded by Pythagoras."

Pythagorean has vowels 'ea' together mispronounced as 'ei'
Word contains consecutive vowels 'EA' in between alphabets pythagor & n is misspelled as 'EI'
Wrong Spelling:  pythagor-ei-n 
Correct Spelling:  pythagor-ea-n 
Find more incorrect spellings of Pythagorean to spell right way.

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