login
Smallest k such that f(f(...f(k))) > 1, where f(k) = A065371(k) is iterated n times.
4

%I #10 Aug 31 2023 02:54:30

%S 5,13,29,43,61,307,383,2689,9209,14897,83557,274679,598333,3516973,

%T 11295673,24104629,229561369

%N Smallest k such that f(f(...f(k))) > 1, where f(k) = A065371(k) is iterated n times.

%C This sequence contains only prime numbers. - _Paul Tek_, Jun 10 2013

%H Paul Tek, <a href="/A065374/a065374.txt">C++ program for this sequence</a>

%e a(2) = 13 because A065372(13) = 3 and A065372(i) = 1 for i < 13.

%e After 10 iterations of A065371 we have a sequence starting with 14896 1's followed by 6, so a(10)= 14897.

%Y Cf. A065371, A065372, A065373.

%K more,nonn

%O 1,1

%A _Reinhard Zumkeller_, Nov 02 2001

%E a(14)-a(16) from _Paul Tek_, Jun 10 2013

%E a(17) from _Sean A. Irvine_, Aug 31 2023