A258980 Primes in A258978.

5, 2801, 22621, 30941, 22621, 637421, 346201, 346201, 346201, 2625641, 837931, 16007041, 3835261, 209102521, 209102521, 15018571, 262209281, 21700501, 30397351, 209102521, 209102521, 693025471, 147753211, 4244897281, 1740422941, 6903678241, 2439903211

Offset

1,1

Comments

These primes are neither sorted nor uniqued. They are listed in the order found in A258978.

Links

Robert Price, Table of n, a(n) for n = 1..932

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

Formula

a(n) = A258978(A258979(n)).

Maple

with(numtheory): A258980:=n->`if`(isprime(1 + sigma(n) + sigma(n)^2 + sigma(n)^3 + sigma(n)^4), 1 + sigma(n) + sigma(n)^2 + sigma(n)^3 + sigma(n)^4, NULL): seq(A258980(n), n=1..300); # Wesley Ivan Hurt, Jul 09 2015

Mathematica

Select[Table[1 + DivisorSigma[1, n] + DivisorSigma[1, n]^2 + DivisorSigma[1, n]^3 + DivisorSigma[1, n]^4, {n, 10000}], PrimeQ]
Select[Table[Cyclotomic[5, DivisorSigma[1, n]], {n, 10000}], PrimeQ]

Prog

(Magma) [m: n in [1..200] | IsPrime(m) where m is (1 + DivisorSigma(1, n) + DivisorSigma(1, n)^2 + DivisorSigma(1, n)^3 + DivisorSigma(1, n)^4)]; // Vincenzo Librandi, Jun 16 2015

Crossrefs

Cf. A000203, A258978, A258979.

Sequence in context: A117011 A367957 A274527 * A096934 A076912 A060041

Adjacent sequences: A258977 A258978 A258979 * A258981 A258982 A258983

Keyword

nonn

Author

Robert Price, Jun 15 2015

Status

approved