

A189994


Length of the longest run of consecutive primes < 10^n that are not Ramanujan primes.


2




OFFSET

1,1


LINKS

Table of n, a(n) for n=1..9.
J. Sondow, Ramanujan primes and Bertrand's postulate Amer. Math. Monthly 116 (2009), 630635.
J. Sondow, J. W. Nicholson, and T. D. Noe, Ramanujan Primes: Bounds, Runs, Twins, and Gaps, J. Integer Seq. 14 (2011) Article 11.6.2.


EXAMPLE

Of the 4 primes < 10^1, the last 3 are not Ramanujan primes, so a(1) = 3.


CROSSREFS

Cf. A104272 (Ramanujan primes), A189993 (length of the longest run of Ramanujan primes < 10^n), A174641 (smallest prime that begins a run of n nonRamanujan primes).
Sequence in context: A029552 A193883 A227038 * A125118 A310008 A299024
Adjacent sequences: A189991 A189992 A189993 * A189995 A189996 A189997


KEYWORD

nonn


AUTHOR

Jonathan Sondow, May 03 2011


STATUS

approved



