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A102813 Numbers n such that n11111111 is prime. 1
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 (list; graph; refs; listen; history; text; internal format)
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 * A271536 A041568 A042305

Adjacent sequences:  A102810 A102811 A102812 * A102814 A102815 A102816

KEYWORD

base,nonn

AUTHOR

Parthasarathy Nambi, Feb 26 2005

STATUS

approved

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Last modified May 28 09:09 EDT 2022. Contains 354112 sequences. (Running on oeis4.)