Next in sequence? oh, ti, ti, ef, ef, es, es, ee,

[Tyler]

After seeing the answer, I still don't get it. Would someone be kind enough to explain? Thanks.

[Staley]

The list is phonetic spellings of letters (o, t, t, f, f...) which are the initials for numbers (1, 2, 3, 4...) so the next is en (n-9).

[Paucle]

Thanks Staley. Yeah, if it had gone to a 24 hr stumper, I'd've added "zee" in front.

[Tyler]

Thank you. Way over my head