A105107 Numbers n such that 10000n + 1001 is prime.

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

Daniel Starodubtsev, Table of n, a(n) for n = 1..10000

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

Adjacent sequences: A105104 A105105 A105106 * A105108 A105109 A105110

Keyword

nonn,easy

Author

Parthasarathy Nambi, Apr 07 2005

Status

approved