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!)
A175766 Greater of "twin numbers": Omega(n) = Omega(n - 2^Omega(n)), where Omega is A001222. 1

%I #4 Mar 31 2012 21:03:15

%S 5,7,10,13,14,19,20,25,26,28,31,38,39,40,43,50,52,55,56,61,62,69,73,

%T 76,78,80,86,91,95,100,103,104,109,110,112,115,119,122,123,124,125,

%U 133,138,139,145,146,151,152,156,159,160,172,181,182,187,190,193,199,200,205,206,208

%N Greater of "twin numbers": Omega(n) = Omega(n - 2^Omega(n)), where Omega is A001222.

%C Generalizes the twin primes. Superset of A006512.

%e "Twin numbers" are (3, 5), (5, 7), (6, 10), (11, 13), (10, 14), (17, 19), (12, 20), (21, 25), (22, 26), (20, 28), (29, 31), (34, 38), (35, 39), (24, 40), (41, 43), (42, 50), (44, 52), (51, 55), (40, 56), (59, 61), (58, 62), (65, 69), (71, 73), ...

%o (PARI) for(n=1,1e3,o=bigomega(n);trap(, ,if(o==bigomega(n-2^o),print1(n","))))

%Y Cf. A001222, A006512, A175612.

%K nonn

%O 1,1

%A _Juri-Stepan Gerasimov_, Sep 01 2010

%E Entry rewritten by _Charles R Greathouse IV_, Sep 01 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 18 02:55 EDT 2024. Contains 371767 sequences. (Running on oeis4.)