A102813 Numbers n such that n11111111 is prime.

17, 35, 36, 39, 42, 48, 50, 74, 80, 92, 95, 105, 120, 122, 128, 135, 141, 170, 171, 203, 206, 218, 239, 249, 255, 263, 276, 284, 287, 300, 311, 332, 333, 338, 351, 386, 398, 401, 414, 417, 419, 449, 450, 468, 483, 486, 498, 507, 512, 515, 524, 531, 534, 569, 575, 576, 581, 615

Offset

1,1

Links

Robert Israel, Table of n, a(n) for n = 1..10000

Example

If n=17, then n11111111 = 1711111111 (prime).
If n=74, then n11111111 = 7411111111 (prime).
If n=128, then n11111111 = 12811111111 (prime).

Maple

select(n -> isprime(10^8*n+11111111), [$1..1000]); # Robert Israel, Feb 24 2017

Mathematica

Select[Range[700], PrimeQ[#*10^8+11111111]&] (* Harvey P. Dale, Sep 25 2015 *)

Prog

(Magma) [ n: n in [1..700] | IsPrime(Seqint([1, 1, 1, 1, 1, 1, 1, 1] cat Intseq(n))) ]; // Vincenzo Librandi, Feb 03 2011

Crossrefs

Sequence in context: A098365 A033899 A110287 * A360573 A271536 A041568

Adjacent sequences: A102810 A102811 A102812 * A102814 A102815 A102816

Keyword

base,nonn

Author

Parthasarathy Nambi, Feb 26 2005

Status

approved