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A105107
Numbers n such that 10000n + 1001 is prime.
3
2, 5, 6, 8, 12, 18, 23, 36, 38, 41, 48, 50, 51, 54, 57, 68, 69, 71, 74, 75, 80, 86, 87, 89, 92, 95, 101, 102, 116, 120, 123, 129, 131, 137, 144, 146, 149, 155, 159, 183, 186, 204, 215, 216, 219, 225, 227, 228, 239, 246, 249, 251, 254, 257, 261, 269, 278, 282
OFFSET
1,1
LINKS
FORMULA
a(n) ~ 0.4n log n.
EXAMPLE
n=2: 21001 is prime.
n=69: 691001 is prime.
PROG
(Magma) [ n: n in [1..300] | IsPrime(Seqint([1, 0, 0, 1] cat Intseq(n))) ];
(PARI) is(n)=isprime(10000*n+1001) \\ Charles R Greathouse IV, Jun 06 2017
CROSSREFS
Sequence in context: A243680 A280381 A333965 * A002253 A032716 A132229
KEYWORD
nonn,easy
AUTHOR
Parthasarathy Nambi, Apr 07 2005
STATUS
approved