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A057437 Numbers k such that 10*7^k + 1 is prime. 1
0, 1, 2, 5, 7, 9, 11, 14, 22, 45, 54, 67, 74, 321, 706, 902, 962, 11393, 13605, 17005, 17364 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

a(22) > 20169. - Jinyuan Wang, Jan 21 2020

LINKS

Table of n, a(n) for n=1..21.

MATHEMATICA

Do[ If[ PrimeQ[ 10*7^n + 1], Print[n]], {n, 1, 1000}]

PROG

(PARI) is(n)=ispseudoprime(10*7^n+1) \\ Charles R Greathouse IV, Jun 12 2017

CROSSREFS

Sequence in context: A169865 A286991 A029905 * A339922 A196255 A024666

Adjacent sequences:  A057434 A057435 A057436 * A057438 A057439 A057440

KEYWORD

nonn,more

AUTHOR

Robert G. Wilson v, Sep 08 2000

EXTENSIONS

First term 0 inserted by and a(18)-a(21) from Jinyuan Wang, Jan 21 2020

STATUS

approved

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Last modified September 18 03:09 EDT 2021. Contains 347504 sequences. (Running on oeis4.)