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a(n) is the largest prime p such that p/PrimePi(p) < n.
0

%I #14 Sep 10 2023 15:29:56

%S 7,31,113,359,1129,3089,8467,24281,64717,175141,481447,1304713,

%T 3524621,9560081,25874773,70119967,189969349,514282961,1394199299,

%U 3779856617,10246936393,27788573801,75370126379,204475055189,554805820519,1505578026059,4086199303001,11091501632977

%N a(n) is the largest prime p such that p/PrimePi(p) < n.

%C Sequence begins at a(2) because there exists no prime p such that p/PrimePi(p) < 1.

%F a(n) = prime(A102281(n)). - _Michel Marcus_, Sep 10 2023

%e a(4) = 113 because 113/PrimePi(113) = 113/30 = 3.766... but p/PrimePi(p) >= 4 for all primes > 113.

%Y Cf. A000720, A038625, A062743, A102281.

%K nonn

%O 2,1

%A _Jon E. Schoenfield_, Sep 09 2023