%I #7 Dec 18 2022 20:04:28
%S 0,0,1,1,2,2,3,3,3,3,4,4,4,4,4,4,5,5,5,5,5,5,5,5,5,5,5,5,6,6,6,6,6,6,
%T 6,6,6,6,6,6,7,7,7,7,7,7,8,8,8,8,8,8,9,9,9,9,9,9,10,10,10,10,10,10,10,
%U 10,10,10,10,10,11,11,11,11,11,11,11,11,11,11,11,11,12,12,12,12
%N a(n) = number of terms of A068811 that are <= n.
%C This is to A068811 as pi = A000720 is to the primes.
%H Michael De Vlieger, <a href="/A359121/b359121.txt">Table of n, a(n) for n = 1..10000</a>
%e A068811 begins 3, 5, 7, ..., so the present sequence begins 0, 0, 1, 1, 2, 2, 3, ..., with an increment as each term of A068811 is reached.
%t c = 0; Reap[Do[If[AllTrue[{n, 10^(1 + Floor@ Log10[n]) - n}, PrimeQ], c++]; Sow[c], {n, 86}]][[-1, -1]] (* _Michael De Vlieger_, Dec 18 2022 *)
%Y Cf. A000720, A068811.
%K nonn
%O 1,5
%A _N. J. A. Sloane_, Dec 18 2022