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%I #6 Jun 09 2019 15:34:13
%S 1,24,3122,823540,285311670608,302875106592250,827240261886336764174,
%T 1978419655660313589123976,20880467999847912034355032910564,
%U 2567686153161211134561828214731016126483466
%N Numbers of the form p^p - 3 where p is prime.
%C Sum of reciprocals = 1.041988188435472536468359944..
%t #^#-3&/@Prime[Range[20]] (* _Harvey P. Dale_, Jun 09 2019 *)
%o (PARI) ptop(n,m) = { sr=0; forprime(x=2,n, y=x^x-m; print1(y","); sr += 1.0/y; ); print(); print(sr) }
%K nonn
%O 1,2
%A _Cino Hilliard_, Nov 23 2003