A083558 p(p^2-p+1) as p runs through the primes.

6, 21, 105, 301, 1221, 2041, 4641, 6517, 11661, 23577, 28861, 49321, 67281, 77701, 101661, 146121, 201957, 223321, 296341, 352941, 383761, 486877, 564981, 697137, 903361, 1020201, 1082221, 1213701, 1283257, 1430241, 2032381, 2231061, 2552721, 2666437

Offset

1,1

Comments

Warning: not all quizzes permit the use of the OEIS!

Discard (from the list of integers) numbers that have exactly 1 factor of prime(n) in their prime factorization. Of those remaining, the proportion that have exactly 2 factors of prime(n) is (prime(n)-1)/a(n). - Peter Munn, Nov 27 2020

Links

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

Formula

a(n) = A000040(n) * A119959(n). - Peter Munn, Nov 29 2020

Mathematica

Table[p(p^2-p+1), {p, Prime[Range[40]]}] (* Harvey P. Dale, Jan 09 2017 *)

Prog

(Magma) [p*(p^2-p+1): p in PrimesUpTo(150)]; // Vincenzo Librandi, Jan 10 2017

Crossrefs

Cf. A000040, A119959.

Sequence in context: A012418 A203295 A318566 * A060843 A026650 A347948

Adjacent sequences: A083555 A083556 A083557 * A083559 A083560 A083561

Keyword

nonn

Author

N. J. A. Sloane, Jun 15 2003

Status

approved