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A335119 Number of positive terms of A082916 not exceeding 10^n. 0

%I

%S 5,33,233,1734,13487,111460,950039,8282970,73631430,662319904,

%T 6022446576,55201746383

%N Number of positive terms of A082916 not exceeding 10^n.

%H Kevin Ford and Sergei Konyagin, <a href="https://arxiv.org/abs/1909.03903">Divisibility of the central binomial coefficient binomial(2n, n)</a>, arXiv:1909.03903 [math.NT], 2019. See Table 2.

%F a(n) ~ c * 10^n/log(10^n), where c = 1.526453... (Ford and Konyagin, 2019).

%e Below 10 there are 5 positive terms of A082916: 1, 3, 5, 7, 9. Therefore a(1) = 5.

%t seqQ[n_] := CoprimeQ[Binomial[2*n, n], n]; seq = {}; p = 10; c = 0; Do[If[seqQ[n], c++]; If[n == p, p *= 10; AppendTo[seq, c]], {n, 1, 10^5}]; seq

%Y Cf. A000984, A082916.

%K nonn,more

%O 1,1

%A _Amiram Eldar_, May 24 2020

%E Terms a(4)-a(11) were taken from the paper by Ford and Konyagin (2019).

%E a(12) from _Giovanni Resta_, May 24 2020

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Last modified June 15 17:41 EDT 2021. Contains 345049 sequences. (Running on oeis4.)