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!)
A161346 a(n) = A161345(n)/3. 6

%I #16 Apr 17 2024 02:35:12

%S 3,4,5,6,7,9,11,13,17,19,23,29,31,37,41,43,47,53,59,61,67,71,73,79,83,

%T 89,97,101,103,107,109,113,127,131,137,139,149,151,157,163,167,173,

%U 179,181,191,193,197,199,211,223,227,229,233,239,241,251,257,263,269,271

%N a(n) = A161345(n)/3.

%C Union of {4, 6, 9} and all the odd primes. - _Amiram Eldar_, Apr 17 2024

%H Michael De Vlieger, <a href="/A161346/b161346.txt">Table of n, a(n) for n = 1..10000</a>

%t Select[Range[271], Function[{n, s}, Max[TakeWhile[Divisors[n], # <= s &]] == 3] @@ {#, Sqrt@ #} &[3 #] &] (* _Michael De Vlieger_, Feb 14 2020 *)

%Y Cf. A018253, A160811, A160812, A161205, A161344, A161345.

%K easy,nonn,changed

%O 1,1

%A _Omar E. Pol_, Jun 20 2009

%E Terms beyond a(10) from _R. J. Mathar_, Jun 24 2009

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 25 01:35 EDT 2024. Contains 371964 sequences. (Running on oeis4.)