"じゃまた"　"またあした"　"またね" And the "ne" works at the end of either of the first two. "Ja mata" "mata ashita" "mata ne" I'm not too sure about a formal setting. Though, またあした would be the most formal of the three. It translates to "again tomorrow?" じゃまた to "well then, again?" and またね "Again, right?"

あとでね。 では後程。（では　のちほど）