%I A090869
%S A090869 613,877,1117,1721,1753,2153,2557,2671,4349,4943,5039,5179,5443,5641,
%T A090869 5939,6037,6827,6997,7591,7853,8069,8209,8527,8669,9221,9311,9377,9859,
%U A090869 10729,11149,11353,11503,11933,12211,12413,12743,12923,13001,13037
%N A090869 Irregular primes whose indices are irregular primes of order one.
%C A090869 The number of primes in this sequence is infinite.
%e A090869 37 is the first irregular prime, 613 is the 37-th irregular prime, i.e.
iprime[iprime[1]] = 613, so 613 is a member.
%o A090869 (PARI) \ Irregular prime index primes. Download the ir12mill2.txt file
from this link into the gp working dir http://groups.yahoo.com/group/
B2LCC/files/Bernoulli/ This was simplified from the table found at
http://www.shokrollahi.com/amin/TAB.html#bernoulli ftp://ftp.reed.edu/
pub/users/jpb/ Start a new PARI session. Default(histsize,310443).
Perform irp12mill2.txt to read in the file.
%o A090869 iprimetable(n) = \ run this only once to produce the iprime[] array {
iprime = vector(310443); for (i = 1, n, iprime[i] = eval( Str("%",
i));) }
%o A090869 ipips(n) = { for(x=1,n, y=iprime[iprime[x]]; \ ipips of order 1 print1(y",
")) }
%Y A090869 Sequence in context: A159641 A100364 A142435 this_sequence A020372 A032657
A117503
%Y A090869 Adjacent sequences: A090866 A090867 A090868 this_sequence A090870 A090871
A090872
%K A090869 easy,nonn
%O A090869 1,1
%A A090869 Cino Hilliard (hillcino368(AT)gmail.com), Feb 12 2004
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