

A276203


Numbers k such that k^9 + 9^k is prime.


0



2, 76, 122, 422, 2300, 5090, 7166, 58046, 91382, 234178, 314738
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OFFSET

1,1


COMMENTS

Numbers k such that A185277(k) is prime.


LINKS

Table of n, a(n) for n=1..11.
Hans Havermann, Indices of A094133 in A076980.
Andrey V. Kulsha, Factorizations of x^y + y^x for 1 < y < x < 151.
P. Leyland, Primes and Strong Pseudoprimes of the form x^y + y^x.


EXAMPLE

2 is a term of the sequence, because A185277(2) = 593 is prime.


PROG

(PARI) is(n) = ispseudoprime(n^9+9^n)


CROSSREFS

Cf. A064539, A185277, A253471.
Sequence in context: A282966 A351433 A351376 * A324216 A198704 A198623
Adjacent sequences: A276200 A276201 A276202 * A276204 A276205 A276206


KEYWORD

nonn,hard,more


AUTHOR

Felix Fröhlich, Aug 27 2016


STATUS

approved



