A133410 Least prime p such that p-6*n is prime.

2, 11, 17, 23, 29, 37, 41, 47, 53, 59, 67, 71, 79, 83, 89, 97, 101, 107, 113, 127, 127, 131, 137, 149, 149, 157, 163, 167, 173, 179, 191, 191, 197, 211, 211, 223, 223, 227, 233, 239, 251, 251, 257, 263, 269, 277, 281, 293, 293, 307, 307, 311, 317, 331, 331, 337

Offset

0,1

Comments

If duplicates are omitted, this is the sequence of primes p such that all p - phi(k) - 1 are composite for 1 <= phi(k)-1 < p. - Michel Lagneau, Sep 14 2012

If duplicates are omitted, the given entries equal A025584 (p: p-2 is not a prime) except A025584 includes 3 (since 1 is not prime). - Harry G. Coin, Nov 29 2015

Links

Robert Israel, Table of n, a(n) for n = 0..10000

Maple

Primes:= select(isprime, {2, seq(i, i=3..10^4, 2)}):
seq(min(Primes intersect map(`+`, Primes, 6*n)), n=0..1000); # Robert Israel, Nov 30 2015

Mathematica

a={}; Do[i=6*n+1; While[Not[PrimeQ[i]&&PrimeQ[i-6*n]], i++ ]; AppendTo[a, i], {n, 0, 60}]; a (* Stefan Steinerberger, Nov 26 2007 *)

Prog

(PARI) a(n) = {k=1; while(k, if(ispseudoprime(prime(k)-6*n), return(prime(k))); k++)} \\ Altug Alkan, Dec 04 2015

Crossrefs

Cf. A025584, A067829 (complement w.r.t. primes), A133387.

Sequence in context: A173638 A018420 A253474 * A156829 A255609 A105840

Adjacent sequences: A133407 A133408 A133409 * A133411 A133412 A133413

Keyword

nonn

Author

Pierre CAMI, Nov 25 2007

Extensions

More terms from Stefan Steinerberger, Nov 26 2007

Status

approved