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A102340
Numbers k such that k3333 is prime.
1
2, 10, 14, 31, 32, 34, 35, 49, 52, 73, 74, 79, 80, 92, 95, 97, 113, 116, 118, 125, 127, 128, 134, 136, 139, 142, 148, 149, 155, 160, 169, 172, 178, 185, 196, 205, 211, 217, 224, 227, 238, 245, 251, 260, 262, 263, 265, 272, 281, 283, 284, 287, 296, 298, 304, 305, 311, 322, 323, 325, 326, 335, 343
OFFSET
1,1
LINKS
EXAMPLE
k=2 is in the sequence because k3333 = 23333 is prime.
k=73 is in the sequence because k3333 = 733333 is prime.
k=125 is in the sequence because k3333 = 1253333 is prime.
MATHEMATICA
Select[Range[500], PrimeQ[FromDigits[Join[IntegerDigits[#], {3, 3, 3, 3}]]]&] (* Harvey P. Dale, Jun 17 2014 *)
Select[Range[500], PrimeQ[#*10^4+3333]&] (* Harvey P. Dale, Jun 15 2024 *)
PROG
(Magma) [ n: n in [1..700] | IsPrime(Seqint([3, 3, 3, 3] cat Intseq(n))) ]; // Vincenzo Librandi, Feb 04 2011
CROSSREFS
Cf. A101472.
Sequence in context: A217191 A190043 A217681 * A358749 A293931 A047043
KEYWORD
nonn,base
AUTHOR
Parthasarathy Nambi, Feb 20 2005
STATUS
approved