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A275523
Numbers k such that 2*10^k + 93 is prime.
0
1, 2, 6, 7, 8, 11, 42, 73, 115, 131, 163, 178, 247, 320, 343, 346, 736, 1230, 1556, 3746, 5946, 6020, 6566, 6770, 11302, 14024, 29062, 33268, 37424, 42187, 49216, 51000, 79242, 81287
OFFSET
1,2
COMMENTS
For k > 1, numbers k such that the digit 2 followed by k-2 occurrences of the digit 0 followed by the digits 93 is prime (see Example section).
a(35) > 10^5.
EXAMPLE
6 is in this sequence because 2*10^6 + 93 = 2000093 is prime.
Initial terms and associated primes:
a(1) = 1, 113;
a(2) = 2, 293;
a(3) = 6, 2000093;
a(4) = 7, 20000093;
a(5) = 8, 200000093, etc.
MATHEMATICA
Select[Range[0, 100000], PrimeQ[2*10^# + 93] &]
PROG
(PARI) is(n)=ispseudoprime(2*10^n+93) \\ Charles R Greathouse IV, Jun 13 2017
KEYWORD
nonn,more
AUTHOR
Robert Price, Jul 31 2016
STATUS
approved