login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A128421 Numbers n such that p(n)# + p(n+1)# +1 is prime, where p(n)# is the product of first n primes (A002110). 7
2, 3, 4, 5, 6, 8, 20, 56, 101, 108, 141, 202, 265, 364, 401, 1035, 1588, 3062, 4191, 4579 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..20.

CROSSREFS

Cf. A002110, A014545, A128420.

Sequence in context: A133706 A081710 A241947 * A115885 A259390 A029964

Adjacent sequences:  A128418 A128419 A128420 * A128422 A128423 A128424

KEYWORD

nonn

AUTHOR

Pierre CAMI, Mar 02 2007

EXTENSIONS

Corrected by Emeric Deutsch, Mar 06 2007

Edited by Ray Chandler, Mar 13 2007

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified May 6 08:22 EDT 2021. Contains 343580 sequences. (Running on oeis4.)