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A103540
Numbers k such that the string k2357111317 is prime.
2
4, 15, 16, 28, 30, 42, 48, 49, 57, 79, 87, 105, 106, 123, 133, 139, 144, 153, 157, 172, 178, 192, 207, 210, 217, 225, 228, 235, 270, 274, 283, 315, 339, 349, 357, 364, 381, 399, 402, 433, 442, 465, 468, 472, 475, 487, 493, 505, 507, 514, 526, 529, 543, 574, 624, 636, 637, 655, 675
OFFSET
1,1
LINKS
EXAMPLE
If k=4, then k2357111317 = 42357111317 (prime).
If k=42, then k2357111317 = 422357111317 (prime).
If k=87, then k2357111317 = 872357111317 (prime).
MATHEMATICA
Select[Range[700], PrimeQ[#*10^10+2357111317]&] (* Harvey P. Dale, Jun 09 2018 *)
PROG
(Magma) [ n: n in [1..700] | IsPrime(Seqint([7, 1, 3, 1, 1, 1, 7, 5, 3, 2] cat Intseq(n))) ]; // Vincenzo Librandi, Feb 03 2011
CROSSREFS
Sequence in context: A228589 A066862 A228590 * A065159 A240265 A051956
KEYWORD
base,nonn
AUTHOR
Parthasarathy Nambi, Mar 23 2005
STATUS
approved