234.
Words, lovely words…
ESSSSE 
(an obsolete word meaning ashes) is in the second edition of the OED.
Double Letter Sequences
Here are some examples words containing double letters, for each letter of the alphabet: AARDVARK, ABBOT,  ACCENT, ADD, FEED,  OFF, EGG, WITHHOLD, SKIING, AVIJJA, BOOKKEEPER, ILL, IMMUNE, ANNOY, HOOPAPPLE, HUQQA, ARRY, KISS, LITTLE, VACUUM, SAVVY, SLOWWORM, WAXXENN, CUBBYYEW and DAZZLE.
Triple Letter Sequences
The following words contain triple letter sequences, uninterrupted by spaces or hyphens. They all appear in at least one English dictionary, but usually as an old spelling or rare variant: 
AAADONTA, FLYINGJIBBBOOM, PEEENT, FREEER,FREEEST, ISHIII, FRILLLESS, 
WALLLESS, LAPAROHYSTEROSALPINGOOOPHORECTOMY, BRRR, GODDESSSHIP, 
COUNTESSSHIP, VERTUUUS, DUCHESSSHIP, HOSTESSSHIPGOVERNESSSHIP, UUULA and YAYYY. Answers.yahoo