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Primes p such that all prime factors of p-1 have exponent 4.
1

%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