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Index of factorial primes of form m!-1.
1

%I #7 Aug 29 2019 09:52:50

%S 3,9,128,675,25306287,3610490805

%N Index of factorial primes of form m!-1.

%F a(n) = PrimePi(A002982(n)!-1) = A000720(A055490(n)).

%e The exact subscript of 7th prime [=30!-1=265252859812191058636308479999999] is not yet available.

%Y Cf. A002981, A002982, A055490.

%K hard,nonn

%O 1,1

%A _Labos Elemer_, Jul 11 2001

%E Offset 1 from _Michel Marcus_, Aug 29 2019