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A281015
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Numbers with a prime number of dots in their International Morse numeral representation.
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5
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2, 3, 5, 7, 8, 11, 12, 14, 16, 18, 19, 20, 21, 23, 25, 27, 29, 30, 32, 34, 36, 38, 41, 43, 47, 49, 50, 52, 58, 61, 63, 67, 69, 70, 72, 74, 76, 78, 80, 81, 83, 85, 87, 89, 91, 92, 94, 96, 98, 99, 101, 102, 104, 106, 108, 109, 110, 111, 113, 115, 117, 119, 120, 122, 124, 126
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OFFSET
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1,1
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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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EXAMPLE
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27 is in the sequence because 27 in its Morse numeral representation is written as '..--- --...' which has 5 dots 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), A280913 (number of dots 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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