A168271 a(n) = prime(nonprime(n)) - nonprime(prime(n)).

1, 3, 5, 9, 7, 9, 12, 16, 14, 13, 17, 20, 17, 21, 25, 25, 21, 21, 17, 19, 35, 32, 28, 31, 25, 31, 33, 33, 39, 47, 33, 30, 47, 49, 39, 39, 37, 43, 44, 44, 43, 41, 38, 48, 58, 59, 47, 35, 50, 58, 55, 59, 71, 64, 61, 61, 62, 71, 75, 71, 81, 75, 62, 63, 69, 70, 57, 63, 59, 61, 63

Offset

1,2

Links

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

Formula

a(n)=A007821(n)-A144570(n).

Crossrefs

Cf. A007821(the "nonprime primes"), A144570(the "prime nonprimes").

Sequence in context: A336849 A348994 A079427 * A081761 A357126 A280702

Adjacent sequences: A168268 A168269 A168270 * A168272 A168273 A168274

Keyword

nonn

Author

Juri-Stepan Gerasimov, Nov 22 2009

Extensions

Corrected (38 replaced by 28, 49 by 59) R. J. Mathar, Jun 04 2010

Status

approved