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A102727
Numbers k such that k1111111 is prime.
0
6, 7, 10, 13, 25, 36, 43, 54, 73, 75, 96, 99, 103, 105, 108, 112, 115, 150, 157, 171, 189, 208, 223, 228, 237, 262, 264, 292, 300, 312, 328, 340, 349, 351, 361, 372, 379, 388, 391, 409, 421, 424, 435, 444, 459, 465, 466, 481, 484, 501, 504, 508, 510, 535, 552, 565, 579, 580, 586, 610, 612, 619
OFFSET
1,1
EXAMPLE
If k=6, then k1111111 = 61111111 (prime).
If k=54, then k1111111 = 541111111 (prime).
If k=108, then k1111111 = 1081111111 (prime).
PROG
(Magma) [ n: n in [1..700] | IsPrime(Seqint([1, 1, 1, 1, 1, 1, 1] cat Intseq(n))) ]; // Vincenzo Librandi, Feb 04 2011
CROSSREFS
Sequence in context: A309854 A083133 A101972 * A315831 A287386 A287803
KEYWORD
base,nonn
AUTHOR
Parthasarathy Nambi, Feb 25 2005
STATUS
approved