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A285016 Primes of the form p*b^b - 1, where p is a prime and b>1. 1
7, 11, 19, 43, 53, 67, 163, 211, 283, 331, 523, 547, 691, 787, 907, 1051, 1123, 1171, 1279, 1531, 1723, 1867, 2011, 2083, 2251, 2347, 2371, 2467, 2707, 2731, 2803, 2971, 3187, 3307, 3547, 3643, 3907, 3931, 4051, 4243, 4363, 4603, 4651, 4723, 5107, 5227 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 1..2300

EXAMPLE

a(1) = 2*(2^2)-1 = 7.

a(2) = 3*(2^2)-1 = 11.

a(3) = 5*(2^2)-1 = 19.

a(4) = 11*(2^2)-1 = 43.

MATHEMATICA

nmax=10^4; pimax=PrimePi[nmax]; bmax=1; While[(bmax+1)^(bmax+1)<=nmax, bmax++]; Select[Union@Flatten@Table[Prime[pi] b^b-1, {b, 2, bmax}, {pi, pimax}], PrimeQ[#]&&#<=nmax&]

CROSSREFS

Cf. A000312, A090866, A285015.

Sequence in context: A165549 A055939 A154555 * A162857 A307965 A323109

Adjacent sequences:  A285013 A285014 A285015 * A285017 A285018 A285019

KEYWORD

nonn,easy

AUTHOR

Vincenzo Librandi, May 12 2017

STATUS

approved

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Last modified February 22 18:24 EST 2020. Contains 332148 sequences. (Running on oeis4.)