A300010 Numbers k such that 3^k + k - 1 is a prime.

1, 3, 65, 123, 435, 465, 677, 947, 4215, 5615

Offset

1,2

Comments

Next term, if it exists, is greater than 10000.

Corresponding primes: 3, 29, 10301051460877537453973547267907, 48519278097689642681155855396759336072749841943521979872949, ...

Links

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

Maple

select(k->isprime(3^k+k-1), [$1..1000]); # Muniru A Asiru, Apr 05 2018

Mathematica

Flatten[{Select[Range[6000], PrimeQ[3^# + # - 1] &]}]

Prog

(Magma) [k: k in [1..700] | IsPrime(3^k+k-1)];
(PARI) lista(nn) = forstep(n=1, nn, 2, if(ispseudoprime(3^n + n - 1), print1(n, ", "))); \\ Altug Alkan, Apr 01 2018

Crossrefs

Cf. A173063, A301632.

Sequence in context: A275044 A205645 A326429 * A196798 A196586 A197043

Adjacent sequences: A300007 A300008 A300009 * A300011 A300012 A300013

Keyword

nonn,more

Author

Vincenzo Librandi, Apr 01 2018

Status

approved