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A272999
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Numbers k such that (11*10^k + 49)/3 is prime.
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0
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1, 2, 4, 5, 7, 10, 11, 16, 18, 21, 22, 30, 41, 69, 83, 128, 166, 190, 262, 263, 353, 496, 1398, 1793, 2806, 9722, 15733, 32420, 61095, 77909, 110496
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OFFSET
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1,2
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COMMENTS
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For k > 1, numbers k such that the digit 3 followed by k-2 occurrences of the digit 6 followed by the digits 83 is prime (see Example section).
a(32) > 3*10^5.
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LINKS
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EXAMPLE
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4 is in this sequence because (11*10^4 + 49)/3 = 36683 is prime.
Initial terms and associated primes:
a(1) = 1, 53;
a(2) = 2, 383:
a(3) = 4, 36683;
a(4) = 5, 366683;
a(5) = 7, 36666683, etc.
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MATHEMATICA
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Select[Range[0, 100000], PrimeQ[(11*10^# + 49)/3] &]
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PROG
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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