

A165557


Primes of the form (p^21)/4p where p are also primes.


2



5, 19, 29, 71, 109, 181, 379, 419, 811, 1259, 1481, 2549, 2861, 3079, 4159, 4691, 7309, 8009, 8929, 13339, 17029, 18089, 19739, 21169, 23869, 24179, 27059, 35531, 37441, 39799, 41411, 43889, 46439, 47741, 48619, 53129, 59779, 61751, 67339, 89101, 93329
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OFFSET

1,1


COMMENTS

The associated primes p are in A165349.


LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..1000


EXAMPLE

a(1) = 5 = (7^21)/47 generated by A165349(1)=7.
a(2) = 19 = (11^21)/411 generated by A165349(2)=11.


MATHEMATICA

Select[Table[(p^2  1)/4  p, {p, Prime[Range[200]]}], PrimeQ] (* Vincenzo Librandi, Oct 12 2012 *)


PROG

(MAGMA) [a: p in PrimesInInterval(5, 700)  IsPrime(a) where a is (p^2  1) div 4  p ]; // Vincenzo Librandi, Oct 12 2012


CROSSREFS

Cf. A165349.
Sequence in context: A115167 A115103 A045457 * A138242 A163076 A122729
Adjacent sequences: A165554 A165555 A165556 * A165558 A165559 A165560


KEYWORD

nonn,easy


AUTHOR

Vincenzo Librandi, Sep 22 2009


EXTENSIONS

Entries checked by R. J. Mathar, Sep 26 2009


STATUS

approved



