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%I #17 Mar 01 2019 03:16:33
%S 2,3,119,127,163,179,191,193,217,219,221,223,239,251,269,311,337,343,
%T 389,403,415,419,427,431,457,491,505,547,557,569,575,581,583,597,599,
%U 613,653,659,667,671,673,683,697,719,739,749,767,779,787,799,807,817
%N Numbers having exactly one partition into two prime powers.
%C A071330(a(n)) = 1.
%H Reinhard Zumkeller, <a href="/A208247/b208247.txt">Table of n, a(n) for n = 1..10000</a>
%o (Haskell)
%o a095841 n = a095841_list !! (n-1)
%o a095841_list = filter ((== 1) . a071330) a000961_list
%o (PARI) is(n)=sum(i=2,n\2,isprimepower(i)&&isprimepower(n-i))+isprimepower(n-1)==1 || n==2 \\ naive; _Charles R Greathouse IV_, Nov 21 2014
%o (PARI) is(n)=my(s); forprime(p=2,n\2,if(isprimepower(n-p) && s++>1, return(0))); for(e=2,log(n)\log(2), forprime(p=2, sqrtnint(n\2,e), if(isprimepower(n-p^e) && s++>1,return(0)))); s+(!!isprimepower(n-1))==1 || n==2 \\ faster; _Charles R Greathouse IV_, Nov 21 2014
%Y A095841 = Intersection of A208247 and A000961.
%K nonn
%O 1,1
%A _Reinhard Zumkeller_, Jan 11 2013
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