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A241861
Primes of the form 2*3^k - k.
1
2, 5, 188286357631, 15018933029959449607893431916515023, 1643356469972045002664087635582629208716484341598400533
OFFSET
1,1
COMMENTS
Generated by k = 0, 1, 23, 71, 113,.. - Michel Marcus, May 11 2014
No other terms for k < 100000. - Jens Kruse Andersen, May 19 2014
EXAMPLE
2 is in this sequence because 2*3^0 - 0 = 2.
MATHEMATICA
Select[Table[2 3^n - n, {n, 0, 300}], PrimeQ] (* Vincenzo Librandi, Oct 21 2014 *)
PROG
(Magma) [a: n in [0..150] | IsPrime(a) where a is 2*3^n - n]; // Juri-Stepan Gerasimov, Apr 30 2014
CROSSREFS
Sequence in context: A247148 A139062 A376895 * A340984 A122760 A358029
KEYWORD
nonn
AUTHOR
STATUS
approved