6週4日目 行こうか行くまいか
Determination・stance・judgment
接続：V辞書＋まい
won't; probably not; negate will
注意 / Note：TWO meanings, look at the subject and distinguish. The subject is the SPEAKER, which is the negative will: determination not to do (二度と遅刻するまい). The subject is OTHERS, which is a negative presumption: probably not (彼は来るまい). Written literature, ancient.
比較 / Compare：Same article: 〜ようか〜まいか／〜ではあるまいか. These models are often mistakenly chosen for each other — carefully read the 接続 and nuances above and then decide.
よく出る形 / Common form：動辞書形＋まい（group one）／動ない形の語幹＋まい（group two:食べまい）。する→するまい・すまい, 来る→来まい.
もう二度と遅刻するまい。
I decided not to be late again.
彼は来るまい。
Maybe they won't come.
同じ失敗は二度と繰り返すまいと心に決めた。
I told myself not to repeat that mistake again.