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!)
A214935 Index of the primes of A205827, A000720(A205827(n)). 9

%I #26 May 16 2014 05:13:27

%S 1,2,4,9,30,189,217,2225,3385,14357,30802,31545,104071,149689,1094421,

%T 1319945,10655462,23163298,112228683,182837804,203615628,486570087,

%U 1094330259,11992433550,17883926781,50070452577,52302956123,72178455400

%N Index of the primes of A205827, A000720(A205827(n)).

%C A000040(a(n)) = A205827(n).

%C With pi(x) being the prime counting function, A000720(x), for n from 1 to 3, a(n) = pi(A111870(n)) = A241542(n), for n from 5 to 28, a(n) = pi(A111870(n-1)) = A241542(n-1). - _John W. Nicholson_, May 10 2014

%H John W. Nicholson, <a href="/A214935/b214935.txt">Table of n, a(n) for n = 1..38</a>

%F a(n) = pi(A205827(n)) = A000720(A205827(n)).

%e a(4) = 9, A000040(9) = 23, and A205827(4) = 23.

%o (PARI) record=0;i=0;A214935=vectorsmall(38);for(n=1,75,current=(A000101[n]/A002386[n]*1.)^A005669[n];if(current>record,record=current;i++;A214935[i]=A005669[n]))

%Y Cf. A205827.

%K nonn

%O 1,2

%A _John W. Nicholson_, Oct 28 2012

%E a(13)-a(28) from _Donovan Johnson_, Oct 28 2012

%E a(29)-a(38) from _John W. Nicholson_, Dec 01 2013

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 March 29 02:23 EDT 2024. Contains 371264 sequences. (Running on oeis4.)