‘Bare infinitives’ are used after conjunction ‘than’.
Example: He has better / read than / to write. / No error
Explanation: According to the rule given above, infinitive with ‘to’ should not be used after conjunction ‘than’. So, there is an error in the third part of the sentence and bare infinitive (write) should be used. Hence, drop ‘to’ from the third part of the sentence and therefore the correct sentence should be:
He has better read than write.