closed sequence

15 LETTERS · STARTS WITH C

closed sequence is a valid 15-letter word worth 28 points in Scrabble and 33 points in Words with Friends.

SCRABBLE WORDS WITH FRIENDS

C3L1O1S1E1D2S1E1Q10U1E1N1C3E1

3 + 1 + 1 + 1 + 1 + 2 + 0 + 1 + 1 + 10 + 1 + 1 + 1 + 3 + 1 =28 PTS

DOUBLE WORD → 56TRIPLE WORD → 84

MEANING

What does closed sequence mean?