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A106808 Numbers n such that 4440011 * 10^n - 1 is prime. 0
12, 44, 75, 237, 3186, 4379, 5535, 6363, 13707, 14463 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

These are primes with square digits and they have all been certified. No more terms up to 37000. Primality proof for the largest: PFGW Version 20041001.Win_Stable (v1.2 RC1b) [FFT v23.8] Primality testing 4440011*10^14463-1 [N+1, Brillhart-Lehmer-Selfridge] Running N+1 test using discriminant 3, base 1+sqrt(3) 4440011*10^14463-1 is prime! (268.8294s+0.0548s)

LINKS

Table of n, a(n) for n=1..10.

R. Ondrejka, The Top Ten: a Catalogue of Primal Configurations.

PROG

(PARI) is(n)=ispseudoprime(4440011*10^n-1) \\ Charles R Greathouse IV, Jun 13 2017

CROSSREFS

Cf. A061246.

Sequence in context: A116187 A009790 A009519 * A296181 A007899 A343729

Adjacent sequences:  A106805 A106806 A106807 * A106809 A106810 A106811

KEYWORD

nonn

AUTHOR

Jason Earls, May 18 2005

STATUS

approved

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Last modified June 24 08:30 EDT 2021. Contains 345416 sequences. (Running on oeis4.)