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A049528
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Number of letters in n-th prime (in English).
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2
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3, 5, 4, 5, 6, 8, 9, 8, 11, 10, 9, 11, 8, 10, 10, 10, 9, 8, 10, 10, 12, 11, 11, 10, 11, 13, 15, 15, 14, 18, 21, 19, 21, 20, 19, 18, 20, 20, 20, 22, 21, 19, 19, 21, 21, 20, 16, 21, 21, 20, 21, 20, 18, 18, 20, 20, 19, 20, 22, 19, 21, 21, 17, 18, 20, 21, 21, 23
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OFFSET
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1,1
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LINKS
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FORMULA
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EXAMPLE
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a(13) = 8 because 'forty-one' contains 8 letters (not counting the hyphen).
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PROG
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(Python)
from sympy import nextprime
from itertools import count, islice
from num2words import num2words as n2w
def f(n): return sum(1 for c in n2w(n).replace(" and", "") if c.isalpha())
def agen(p=2):
while True: yield f(p); p = nextprime(p)
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CROSSREFS
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KEYWORD
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easy,nice,nonn,word
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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