login
Numbers of the form p^q^r, for p,q,r primes.
2

%I #13 Apr 23 2013 11:15:47

%S 16,81,256,512,625,2401,6561,14641,19683,28561,83521,130321,279841,

%T 390625,707281,923521,1874161,1953125,2825761,3418801,4879681,5764801,

%U 7890481,12117361,13845841,20151121,25411681,28398241,33554432,38950081,40353607,47458321

%N Numbers of the form p^q^r, for p,q,r primes.

%C Subset of A217261. Sequence suggested by _Kevin L. Schwartz_ in a Facebook discussion.

%e a(1) = 2^2^2 = 16;

%e a(2) = 3^2^2 = 81;

%e a(3) = 2^2^3 = 256;

%e a(4) = 2^3^2 = 512;

%e a(5) = 5^2^2 = 625.

%Y Cf. A000040, A000961, A217261.

%K nonn,easy

%O 1,1

%A _Jonathan Vos Post_, Mar 20 2013

%E More terms from _Alois P. Heinz_, Mar 20 2013