login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A177193 The twin primes p such that m and k are also twin primes where m*k=semiprime(p). 0

%I #3 Mar 30 2012 18:52:40

%S 3,7,11,13,17,19,31,43,59,61,71,101,103,139,179,311,313,347,349,421,

%T 463,523,569,571,599,601,617,659,823,1019,1021,1031,1061,1093,1153,

%U 1319,1321,1429,1619,1667,1697,1721,1787,1789

%N The twin primes p such that m and k are also twin primes where m*k=semiprime(p).

%e a(1)=3 because 3*3=semiprime(3) and 3=twin prime, a(2)=7 because 3*7=semiprime(7) and 3,7 are twin primes.

%Y Cf. A001097, A001358, A084126, A084127.

%K nonn

%O 1,1

%A _Juri-Stepan Gerasimov_, May 04 2010

%E Entries checked and sequence extended beyond 139 - _R. J. Mathar_, May 06 2010

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified April 24 15:18 EDT 2024. Contains 371960 sequences. (Running on oeis4.)