

A141061


Number of primes between n*p(n) and (n+1)*p(n+1), where p(n) is the nth prime.


0



2, 3, 3, 7, 5, 9, 6, 10, 15, 7, 18, 13, 11, 16, 20, 22, 16, 21, 18, 19, 28, 22, 29, 39, 21, 23, 25, 17, 31, 69, 28, 40, 23, 56, 24, 45, 42, 38, 48, 45, 30, 64, 30, 46, 29, 88, 82, 44, 33, 42, 60, 40, 81, 59, 60, 69, 39, 64, 49, 42, 95, 110, 59, 47, 56, 134, 70, 106, 49, 55, 77
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OFFSET

1,1


LINKS

Table of n, a(n) for n=1..71.


EXAMPLE

a(4)=7 because between 4*p(4)=4*7=28 and 5*p(5)=5*11=55 one has 7 primes (29,31,37,41,43,47 and 53).


MAPLE

with(numtheory): seq(pi((n+1)*ithprime(n+1))pi(n*ithprime(n)), n=1..74); # Emeric Deutsch, Aug 16 2008


CROSSREFS

Sequence in context: A342878 A209574 A079387 * A256447 A076557 A228548
Adjacent sequences: A141058 A141059 A141060 * A141062 A141063 A141064


KEYWORD

nonn


AUTHOR

JuriStepan Gerasimov, Aug 04 2008


EXTENSIONS

Corrected and extended by Emeric Deutsch, Aug 16 2008


STATUS

approved



