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A085557
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Numbers that have more prime digits than nonprime digits.
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5
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2, 3, 5, 7, 22, 23, 25, 27, 32, 33, 35, 37, 52, 53, 55, 57, 72, 73, 75, 77, 122, 123, 125, 127, 132, 133, 135, 137, 152, 153, 155, 157, 172, 173, 175, 177, 202, 203, 205, 207, 212, 213, 215, 217, 220, 221, 222, 223, 224, 225, 226, 227, 228, 229, 230, 231, 232
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listen;
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text;
internal format)
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OFFSET
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1,1
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COMMENTS
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Begins to differ from A046034 at the 21st term (which is the first 3-digit term).
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LINKS
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EXAMPLE
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133 is in the sequence as the prime digits are 3 and 3 (those are two digits; counted with multiplicity) and one nonprime digit 1 and so there are more prime digits than nonprime digits. - David A. Corneth, Sep 06 2020
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PROG
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(PARI) is(n) = my(d = digits(n), c = 0); for(i = 1, #d, if(isprime(d[i]), c++)); c<<1 > #d \\ David A. Corneth, Sep 06 2020
(Python)
from itertools import count, islice
def A085557_gen(startvalue=1): # generator of terms
return filter(lambda n:len(s:=str(n))<(sum(1 for d in s if d in {'2', '3', '5', '7'})<<1), count(max(startvalue, 1)))
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CROSSREFS
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Cf. A193238, A046034, A046035, A118950, A019546, A203263, A035232, A039996, A085823, A052382, A084544, A084984, A017042, A001743, A001744, A014261, A014263, A202267, A202268, A211681.
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KEYWORD
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nonn,easy,base,changed
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AUTHOR
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STATUS
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approved
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