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A274986
Numbers k such that (10^k + 23)/3 is prime.
1
1, 2, 6, 146, 326, 380, 1116, 1866, 4808, 5528, 5730, 21836, 24804, 38724
OFFSET
1,2
COMMENTS
Also numbers k for which A093137(k) + 7 or A002277(k) + 8 is prime.
MATHEMATICA
Select[Range[1000], PrimeQ[(10^# + 23) / 3] &]
PROG
(Magma) [n: n in [0..400] | IsPrime((10^n+23) div 3)];
(PARI) is(n)=ispseudoprime((10^n+23)/3) \\ Charles R Greathouse IV, Jun 13 2017
CROSSREFS
Cf. numbers k such that (10^k+m)/3 is prime: A099411 (m=11), this sequence (m=23).
Sequence in context: A280714 A164764 A333444 * A024397 A099185 A015173
KEYWORD
nonn,less,more
AUTHOR
Vincenzo Librandi, Sep 25 2016
EXTENSIONS
a(9)-a(11) from Michael S. Branicky, Aug 16 2021
a(12)-a(13) from Michael S. Branicky, May 14 2023
a(14) from Kamada data by Tyler Busby, May 05 2024
STATUS
approved