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A259186 Primes in A259184. 3
7, 13, 43, 31, 211, 157, 307, 757, 307, 1483, 1723, 3541, 1723, 5113, 3907, 8191, 3541, 8011, 1723, 6007, 5113, 5113, 14281, 5113, 14281, 8011, 3541, 28057, 20593, 20593, 5113, 37831, 28057, 17293, 14281, 8011, 12433, 28057, 20593, 14281, 24181, 10303, 46441 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

These primes are neither sorted nor uniqued. They are listed in the order found in A259184.

LINKS

Robert Price, Table of n, a(n) for n = 1..1737

OEIS Wiki, Cyclotomic Polynomials at x=n, n! and sigma(n)

FORMULA

a(n) = A259184(A259185(n)).

MAPLE

with(numtheory): A259186:=n->`if`(isprime(1 - sigma(n) + sigma(n)^2), 1 - sigma(n) + sigma(n)^2, NULL): seq(A259186(n), n=1..200); # Wesley Ivan Hurt, Jul 09 2015

MATHEMATICA

Select[Table[1 - DivisorSigma[1, n] + DivisorSigma[1, n]^2, {n, 10000}], PrimeQ]

Select[Table[Cyclotomic[6, DivisorSigma[1, n]], {n, 10000}], PrimeQ]

CROSSREFS

Cf. A000203, A259184, A259185.

Sequence in context: A097444 A241718 A259184 * A151781 A224502 A047977

Adjacent sequences:  A259183 A259184 A259185 * A259187 A259188 A259189

KEYWORD

easy,nonn

AUTHOR

Robert Price, Jun 20 2015

STATUS

approved

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Last modified December 6 07:00 EST 2019. Contains 329784 sequences. (Running on oeis4.)