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Number of nonprimes among first n terms of A090252.
4

%I #7 May 31 2022 23:43:56

%S 1,1,1,1,2,2,3,3,3,3,4,4,4,5,6,6,6,6,6,6,6,6,7,7,7,7,7,7,8,8,9,10,10,

%T 10,10,10,10,10,10,10,10,10,10,10,10,10,11,11,11,11,11,11,11,11,11,11,

%U 11,11,12,13,13,13,14,14,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,15,16,17

%N Number of nonprimes among first n terms of A090252.

%C It appears that this sequence controls the growth of A090252. That is, almost all the terms of A090252 lie on the line A090252(n) = k-th prime, where k = n - a(n).

%H N. J. A. Sloane, <a href="/A354166/b354166.txt">Table of n, a(n) for n = 1..34886</a>

%Y Cf. A090252, A354164, A354165.

%K nonn

%O 1,5

%A _N. J. A. Sloane_, May 31 2022