A227199 Primes that divide some term of A006720.

2, 3, 7, 11, 23, 41, 47, 53, 59, 61, 71, 73, 83, 97, 101, 113, 127, 139, 149, 157, 173, 179, 181, 191, 197, 199, 211, 223, 229, 239, 257, 263, 271, 277, 281, 307, 331, 337, 347, 359, 373, 379, 383, 389, 397, 409, 419, 433, 439, 443, 463, 467, 479, 499, 509

Offset

1,1

Comments

The density of primes in this sequence is 11/21.

If p divides A006720(n) for some n, then the smallest such n is <= (1/2)*((sqrt(p)+1)^2+3).

Links

Jeremy Rouse, Table of n, a(n) for n = 1..10000

R. Jones and J. Rouse, Galois Theory of Iterated Endomorphisms, Proceedings of the London Mathematical Society, 100, no. 3 (2010), 763-794.

Example

11 is in the sequence because 11 divides A006720(10) = 1529.

Prog

(Magma) [ n : n in [2..500] | IsPrime(n) and (n ne 37) and (Order(EllipticCurve([GF(n)!0, 0, 1, -1, 0])![0, 0, 1]) mod 2 eq 1) ];

Crossrefs

Sequence in context: A039787 A267503 A226937 * A129940 A128631 A092217

Adjacent sequences: A227196 A227197 A227198 * A227200 A227201 A227202

Keyword

easy,nonn

Author

Jeremy Rouse, Sep 18 2013

Status

approved