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A072685
Positive integers whose English names contain a prime number of letters.
4
1, 2, 3, 6, 7, 8, 10, 15, 16, 23, 27, 28, 33, 37, 38, 40, 50, 60, 70, 74, 75, 79, 83, 87, 88, 93, 97, 98, 104, 105, 109, 111, 112, 120, 124, 125, 129, 130, 134, 135, 139, 143, 147, 148, 153, 157, 158, 163, 167, 168, 171, 172, 176, 180, 184, 185, 189, 190, 194, 195
OFFSET
1,2
EXAMPLE
First value is 1 because 1 -> "ONE" -> 3 letters and 3 is prime. Numbers >100 use naming convention using "and": 199 -> "ONEHUNDREDANDNINETYNINE" -> 23 letters and 23 is prime.
CROSSREFS
Sequence in context: A179794 A221977 A001162 * A119960 A273265 A015841
KEYWORD
easy,nonn,word
AUTHOR
Mark Hudson (mrmarkhudson(AT)hotmail.com), Jul 02 2002
STATUS
approved