

A050522


Primes of form 5*2^n1.


4



19, 79, 1279, 5119, 20479, 81919, 1310719, 21474836479, 1407374883553279, 90071992547409919, 23611832414348226068479, 1784059615882449851322857461811868920478433279
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OFFSET

1,1


LINKS

Table of n, a(n) for n=1..12.
Heiko Harborth, On hperfect numbers, Annales Mathematicae et Informaticae, 41 (2013) pp. 5762.
Index entries for sequences of n such that k*2^n1 (or k*2^n+1) is prime


MATHEMATICA

Select[Table[5*2^n1, {n, 0, 150}], PrimeQ] (* JeanFrançois Alcover, Mar 21 2011 *)


CROSSREFS

See A001770 for more terms.
Sequence in context: A139941 A127270 A053665 * A172973 A212056 A290224
Adjacent sequences: A050519 A050520 A050521 * A050523 A050524 A050525


KEYWORD

nonn,nice


AUTHOR

N. J. A. Sloane, Dec 29 1999


STATUS

approved



