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A109397 Numbers n such that 22 * 10^n + 1 is prime. 0
0, 6, 10, 11, 102, 146, 296, 1415, 2324, 4374, 12590 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

All terms have been certified. Primality proof for the largest: PFGW Version 1.2.0 for Windows [FFT v23.8] Primality testing 22*10^12590+1 [N-1, Brillhart-Lehmer-Selfridge] Running N-1 test using base 3 Calling Brillhart-Lehmer-Selfridge with factored part 69.89% 22*10^12590+1 is prime! (47.5292s+0.3107s)

No more terms up to 31000.

LINKS

Table of n, a(n) for n=1..11.

PROG

(PARI) is(n)=ispseudoprime(22*10^n+1) \\ Charles R Greathouse IV, Jun 13 2017

CROSSREFS

Cf. A056807.

Sequence in context: A096549 A248757 A136812 * A133210 A141467 A105642

Adjacent sequences:  A109394 A109395 A109396 * A109398 A109399 A109400

KEYWORD

more,nonn

AUTHOR

Jason Earls, Aug 26 2005

EXTENSIONS

0 added by Arkadiusz Wesolowski, Oct 27 2011

STATUS

approved

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Last modified February 22 18:00 EST 2018. Contains 299469 sequences. (Running on oeis4.)