|
%I #16 Jan 19 2020 13:31:56
%S 17,41,73,89,97,109,113,137,163,193,233,241,251,257,271,281,313,337,
%T 353,379,401,409,433,449,457,487,521,541,569,577,593,601,617,641,673,
%U 751,757,761,769,809,811,857,881,919,929,937,953,977
%N Primes p such that p-1 is divisible by a cube.
%H Daniel Starodubtsev, <a href="/A089200/b089200.txt">Table of n, a(n) for n = 1..10000</a>
%t f[n_]:=Max[Last/@FactorInteger[n]]; lst={};Do[p=Prime[n];If[f[p-1]>=3,AppendTo[lst,p]],{n,6!}];lst (* _Vladimir Joseph Stephan Orlovsky_, Oct 03 2009 *)
%t Select[Prime[Range[200]],Count[Transpose[FactorInteger[#-1]][[2]], _?(#>2&)]>0&] (* _Harvey P. Dale_, Jan 01 2012 *)
%o (PARI) powerfreep3(n,p,k) = { c=0; pc=0; forprime(x=2,n, pc++; if(ispowerfree(x+k,p)==0, c++; print1(x","); ) ); print(); print(c","pc","c/pc+.0) } ispowerfree(m,p1) = { flag=1; y=component(factor(m),2); for(i=1,length(y), if(y[i] >= p1,flag=0;break); ); return(flag) }
%K easy,nonn
%O 1,1
%A _Cino Hilliard_, Dec 08 2003
|
