

A274336


Numbers k such that (16*10^k  91)/3 is prime.


0



1, 2, 3, 5, 16, 18, 22, 31, 40, 98, 99, 192, 233, 367, 501, 1102, 1381, 1416, 2018, 6156, 6860, 7377, 14004, 16634, 21422, 27654, 85473, 260256, 265052, 274251
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OFFSET

1,2


COMMENTS

For k > 1, numbers k such that the digit 5 followed by k1 occurrences of the digit 3 followed by the digits 03 is prime (see Example section).
a(31) > 3*10^5.


LINKS



EXAMPLE

3 is in this sequence because (16*10^3  91)/3 = 5303 is prime.
Initial terms and associated primes:
a(1) = 1, 23;
a(2) = 2, 503;
a(3) = 3, 5303;
a(4) = 5, 533303;
a(5) = 16, 53333333333333303, etc.


MATHEMATICA

Select[Range[0, 100000], PrimeQ[(16*10^#  91)/3] &]


PROG



CROSSREFS



KEYWORD

nonn,more


AUTHOR



EXTENSIONS



STATUS

approved



