

A262937


Numbers n such that (28*10^n  13) / 3 is prime.


0



0, 1, 2, 4, 5, 8, 10, 14, 17, 20, 33, 64, 80, 152, 158, 166, 194, 196, 198, 901, 971, 1289, 1595, 2921, 14390, 28781, 35840
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OFFSET

1,3


COMMENTS

For n>1, numbers such that the digit 9 followed by n2 occurrences of the digit 3 followed by the digits 29 is prime (see Example section).
a(28) > 10^5.


LINKS

Table of n, a(n) for n=1..27.
Makoto Kamada, Factorization of nearrepdigitrelated numbers.
Makoto Kamada, Search for 93w29.


EXAMPLE

2 is in this sequence because (28*10^2  13) / 3 = 929 is prime.
Initial terms and primes associated:
a(1) = 0, 5;
a(2) = 1, 89;
a(3) = 2, 929;
a(4) = 4, 93329;
a(5) = 5, 933329, etc.


MATHEMATICA

Select[Range[0, 100000], PrimeQ[(28*10^#  13) / 3] &]


PROG

(PARI) is(n)=ispseudoprime((28*10^n13)/3) \\ Charles R Greathouse IV, Jun 13 2017


CROSSREFS

Cf. A056654, A268448, A269303, A270339, A270613, A270831, A270890, A270929, A271269.
Sequence in context: A067941 A182195 A092265 * A249508 A163295 A101274
Adjacent sequences: A262934 A262935 A262936 * A262938 A262939 A262940


KEYWORD

nonn,more


AUTHOR

Robert Price, Sep 23 2016


STATUS

approved



