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Table of n, a(n) for n=1..58.
a(n) = PrimePi(A030432(n-1)).
Select[Range, Mod[Prime[ # ], 10] == 7 &] (*Chandler*)
Cf. A030432, A102342.
Sequence in context: A085048 A024813 A244741 * A026360 A237514 A047535
Adjacent sequences: A049506 A049507 A049508 * A049510 A049511 A049512
N. J. A. Sloane.
Extended by Ray Chandler, Nov 07 2006