A217671 a(n) is the least prime of the set of the smallest n consecutive primes a(n)=q_1(n), q_2(n),..., such that between (1/2)*q_i and (1/2)q_(i+1), i=1,...,n-1, there exists a prime, or a(n)=0 if no such set of primes exists.

3, 3, 3, 73, 523, 6581, 10753, 43103, 43103, 43103, 55457, 55457, 28751773, 278689963, 278689963, 784284211, 4440915607, 8340839629, 30651695947, 50246427391, 50246427391

Offset

2,1

Comments

If a(N) = 0, then a(n) = 0 for n > N. Conjecture 39 in the Shevelev link says that a(n) > 0.

Links

Table of n, a(n) for n=2..22.

V. Shevelev, Ramanujan and Labos primes, their generalizations, and classifications of primes, J. Integer Seq. 15 (2012) Article 12.5.4

Crossrefs

Cf. A166251, A182405, A182523, A182426.

Sequence in context: A340821 A091323 A174641 * A118539 A015665 A343120

Adjacent sequences: A217668 A217669 A217670 * A217672 A217673 A217674

Keyword

nonn

Author

Vladimir Shevelev, Oct 10 2012

Extensions

a(14) from John W. Layman and Hans Havermann

a(15)-a(17) from Carlos Rivera and Hans Havermann

a(18)-a(20) from Hans Havermann

a(21)-a(22) from Donovan Johnson, Oct 17 2012

Status

approved