A136611 = wrong version of A058009

Maximilian Hasler maximilian.hasler at gmail.com
Mon Apr 28 06:25:33 CEST 2008


%S A136611 2,3,5,31,277,5381,87803
%N A136611 a(n) = P(k) iterated n times , starting from k = n =
P(P(P(. . . (P(n)). . . )));
               where P(k) = A000040(k) = k-th prime.
%e A136611 P(3)=5; P(5)=11, P(11)=31, hence a(3)= 31
%A A136611 Philippe Lallouet (philip.lallouet(AT)orange.fr), Apr 14 2008

is not correct (31 should be a(3), not a(4), cf. example;
p(2)=3,p(3)=5=a(2), p(1)=2=a(1));
it should be the same as A058009 given below; but the %N A058009 could
be made more explicit, e.g.
%N A058009 a(n) = A000040(...A000040(n)...): A000040 applied n times to n.
and one coud add:
%Y A058009 Cf. A007097(k+1)=A000040(A007097(k)).
and in principle one could pre-pend a(0)=0.
M.H.

%S A058009 2,5,31,277,5381,87803,2269733,50728129,1559861749,64988430769,
%T A058009 2428095424619
%N A058009 An iterative sequence of primes.
%e A058009 a(3) is 31 because the third prime is 5, the fifth prime is
11 and for the 3rd interation,
               the eleventh prime is 31.
%t A058009 Table[ Nest[ Prime, n, n ], {n, 1, 11} ]
%Y A058009 Adjacent sequences: A058006 A058007 A058008 this_sequence
A058010 A058011 A058012
%Y A058009 Sequence in context: A119242 A068145 A032112 this_sequence
A097396 A056788 A091859
%K A058009 nonn
%O A058009 1,1
%A A058009 Robert G. Wilson v (rgwv(AT)rgwv.com), Nov 13 2000





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