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%I #10 Jun 19 2022 15:15:13
%S 1,1,1,1,2,2,2,2,2,3,3,3,3,3,3,3,3,3,4,4,4,4,4,4,4,4,4,4,4,4,5,5,5,5,
%T 5,5,5,5,5,5,5,5,5,5,5,5,5,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,6,
%U 7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,7,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8,8
%N Floor of cube root of n-th prime.
%F a(n) = A048766(A000040(n)). - _Michel Marcus_, Nov 10 2015
%t Floor[Surd[#,3]]&/@Prime[Range[120]] (* _Harvey P. Dale_, Jun 19 2022 *)
%o (PARI) a(n) = sqrtnint(prime(n), 3); \\ _Michel Marcus_, Nov 10 2015
%Y Cf. A000006, A000196, A048766.
%K nonn
%O 1,5
%A _N. J. A. Sloane_, Nov 09 2015