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!)
A161763 Product of the two primes with indices equal to the members of the n-th twin prime pair. 0
55, 187, 1271, 3953, 13843, 34189, 78391, 129551, 307961, 351613, 616081, 753343, 1155481, 1350163, 1461617, 2073551, 2282977, 2999743, 3367081, 4293103, 5503691, 8427373, 9060019, 10751441, 14039813, 17164349, 19439137, 20775283, 22781333 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..29.

FORMULA

a(n)=A000040(A001359(n))*A000040(A006519(n)).

EXAMPLE

prime(3)*prime(5)=55. prime(5)*prime(7) = 187. prime(11)*prime(13)=1271. prime(17)*prime(19)=3953.

MATHEMATICA

Prime[First[#]] Prime[Last[#]]&/@Select[Partition[Prime[Range[200]], 2, 1], Last[#]-First[#]==2&]  (* Harvey P. Dale, Feb 22 2011 *)

CROSSREFS

Cf. A000040, A001359, A006519.

Sequence in context: A039781 A135657 A178793 * A189005 A105442 A158646

Adjacent sequences:  A161760 A161761 A161762 * A161764 A161765 A161766

KEYWORD

nonn

AUTHOR

Juri-Stepan Gerasimov, Jun 18 2009

EXTENSIONS

Corrected by R. J. Mathar, Oct 21 2009

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 March 28 10:27 EDT 2020. Contains 333082 sequences. (Running on oeis4.)