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A249394
Numbers k such that the k-th ménage number is prime.
1
4, 5, 13, 53, 8645
OFFSET
1,1
COMMENTS
This sequence is heuristically conjectured to grow doubly-exponentially.
a(6) > 100000. - Hans Havermann, Jan 19 2019
LINKS
Adam P. Goucher, Menage primes, Complex Projective 4-Space.
EXAMPLE
The only known ménage primes are M(4) = 2, M(5) = 13, M(13) = 775596313, M(53) = 567525075138663383127158192994765939404930668817780601409606090331861, and M(8645).
PROG
(PARI) is(n)=ispseudoprime(round(2*n*exp(-2)*besselk(n, 2))) \\ Charles R Greathouse IV, Nov 10 2014
CROSSREFS
By definition, the inverse image of A000040 under the function A000179.
The ménage primes themselves are given in A249510.
Sequence in context: A272898 A102981 A257487 * A295278 A029663 A251723
KEYWORD
nonn,hard
AUTHOR
Adam P. Goucher, Oct 30 2014
EXTENSIONS
Example edited by Hans Havermann, Jan 19 2019
STATUS
approved