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%I #15 Dec 07 2012 16:35:32
%S 2,5,7,23,47,167,359,839,1367,1847,2207,3719,5039,7919,8179,10607,
%T 11447,16127,17159,19319,29927,36479,44519,49727,54287,57119,66047,
%U 85847,97967,113567,128879,177239,196247,201599,218087,241079,273527,292679,323759,344567
%N Primes of the form p^q - q, where p and q are primes.
%F Union of A049002 and A057678.
%e 8179 = 2^13 - 13
%t nn = 600000; mx = Floor[Log[2, nn]]; t2 = Select[Table[2^n - n, {n, Prime[Range[PrimePi[mx]]]}], PrimeQ]; mx = Floor[Sqrt[nn]]; tp = Select[Table[n^2 - 2, {n, Prime[Range[PrimePi[mx]]]}], PrimeQ]; Union[t2, tp] (* _T. D. Noe_, May 01 2012 *)
%t Module[{upto=350000,r},r=Floor[Sqrt[upto+2]];Select[Union[Select[ (#1[[1]]^#1[[2]]-#1[[2]]&)/@Tuples[Prime[Range[r]],2], PrimeQ]], #1<=upto&]] (* _Harvey P. Dale_, Dec 07 2012 *)
%Y Cf. A049002 (primes of the form p^2 - 2).
%Y Cf. A057678 (primes of the form 2^p - p).
%K nonn,easy
%O 1,1
%A _Alex Ratushnyak_, May 01 2012
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