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A281017
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Numbers with a prime number of dashes in their International Morse numeral representation.
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5
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0, 2, 3, 7, 8, 12, 14, 16, 18, 21, 23, 25, 27, 29, 30, 32, 34, 35, 36, 38, 41, 43, 44, 46, 47, 49, 50, 52, 53, 57, 58, 61, 63, 64, 66, 67, 69, 70, 72, 74, 75, 76, 78, 81, 83, 85, 87, 89, 92, 94, 96, 98, 101, 103, 107, 109, 110, 112, 118, 121, 125, 129, 130, 134, 136, 143
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OFFSET
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1,2
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COMMENTS
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The Morse code is written in current ITU standard.
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LINKS
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FORMULA
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EXAMPLE
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27 is in the sequence because 27 in its Morse numeral representation is written as '..--- --...' which has 5 dashes and 5 is prime.
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PROG
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from sympy import isprime
i=0
j=1
while j<=100:
print(str(j)+" "+str(i))
j+=1
i+=1
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CROSSREFS
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Cf. A060109 (Morse code for n), A280916 (number of dashes in Morse code for n).
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KEYWORD
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nonn,base
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AUTHOR
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STATUS
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approved
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