

A110949


Integers n such that 4*10^n + 61 is prime.


0



1, 2, 7, 11, 191, 248, 1067, 2666, 5252, 13400, 22886, 23739, 29095
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OFFSET

1,2


COMMENTS

See Kamada link  primecount.txt for terms, primesize.txt for discovery details including probable or proved primes  search on "40061".
a(14) > 10^5.  Robert Price, Jan 22 2017


LINKS

Table of n, a(n) for n=1..13.
Makoto Kamada, List of nearrepdigitrelated prime numbers.
Index entries for primes involving repunits.


EXAMPLE

n = 7 is in the sequence because 4*10^7 + 61 = 4*10000000 + 61 = 40000000 + 61 = 40000061, which is prime.


PROG

(PARI) isok(n) = isprime(4*10^n+61); \\ Michel Marcus, Jan 22 2017


CROSSREFS

Cf. A049054, A088274, A088275, A095688, A107083, A108049, A108050, A108052, A108054.
Sequence in context: A069885 A069748 A064441 * A226703 A126343 A174539
Adjacent sequences: A110946 A110947 A110948 * A110950 A110951 A110952


KEYWORD

more,nonn


AUTHOR

Julien Peter Benney (jpbenney(AT)ftml.net), Oct 04 2005


EXTENSIONS

a(9)a(11) from Ray Chandler, Dec 23 2010
Prepended a(1)=1 by Robert Price, Jan 22 2017
a(12)a(13) from Robert Price, Jan 22 2017


STATUS

approved



