%I #10 Mar 30 2012 18:52:14
%S 17,1297,1336337,4477457,29986577,45212177,126247697,193877777,
%T 406586897,562448657,916636177,1416468497,1944810001,3208542737,
%U 4162314257,5006411537,5972816657,12444741137,19565295377,34188010001,38167092497
%N Primes p such that all prime factors of p-1 have exponent 4.
%e 17-1=2^4, 1297-1=2^4*3^4, 1336337-1=2^4*17^4, 4477457-1=2^4*23^4,...
%t Select[Table[Prime[n],{n,600000}],Length[Union[Last/@FactorInteger[#-1]]]==1&&Union[Last/@FactorInteger[#-1]]=={4}&]
%Y Cf. A089195 (exponent 2), A037896 (primes n^4+1).
%K nonn
%O 1,1
%A _Vladimir Joseph Stephan Orlovsky_, Apr 09 2011
%E a(11)-a(21) from _Donovan Johnson_, Apr 10 2011