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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A290743 Maximum number of distinct Lyndon factors that can appear in words of length n over an alphabet of size 2.

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%I A290743 #40 Sep 16 2022 03:55:39
%S A290743 2,3,4,6,8,11,14,18,22,27,32,38,44,51,58,66,74,83,92,102,112,123,134,
%T A290743 146,158,171,184,198,212,227,242,258,274,291,308,326,344,363,382,402,
%U A290743 422,443,464,486,508,531,554,578,602,627,652,678,704,731,758
%N A290743 Maximum number of distinct Lyndon factors that can appear in words of length n over an alphabet of size 2.
%C A290743 See theorem 1 of reference for formula.
%H A290743 Vincenzo Librandi, <a href="/A290743/b290743.txt">Table of n, a(n) for n = 1..1000</a>
%H A290743 Amy Glen, Jamie Simpson, and W. F. Smyth, <a href="https://doi.org/10.37236/6915">Counting Lyndon Factors</a>, Electronic Journal of Combinatorics 24(3) (2017), #P3.28.
%H A290743 Ryo Hirakawa, Yuto Nakashima, Shunsuke Inenaga, and Masayuki Takeda, <a href="https://arxiv.org/abs/2106.01190">Counting Lyndon Subsequences</a>, arXiv:2106.01190 [math.CO], 2021. See MDF(n, s).
%H A290743 <a href="/index/Rec#order_04">Index entries for linear recurrences with constant coefficients</a>, signature (2,0,-2,1).
%F A290743 a(n) = binomial(n+1,2) - (s-p)*binomial(m+1,2) - p*binomial(m+2,2) + s where s=2, m=floor(n/s), p=n-m*s. - _Andrew Howroyd_, Aug 14 2017
%F A290743 From _Colin Barker_, Oct 03 2017: (Start)
%F A290743 G.f.: x*(2 - x - 2*x^2 + 2*x^3) / ((1 - x)^3*(1 + x)).
%F A290743 a(n) = (2*n^2 + 16) / 8 for n even.
%F A290743 a(n) = (2*n^2 + 14) / 8 for n odd.
%F A290743 a(n) = 2*a(n-1) - 2*a(n-3) + a(n-4) for n > 4. (End)
%F A290743 E.g.f.: ((8 + x + x^2)*cosh(x) + (7 + x + x^2)*sinh(x) - 8)/4. - _Stefano Spezia_, Jul 06 2021
%F A290743 Sum_{n>=1} 1/a(n) = coth(sqrt(2)*Pi)*Pi/(2*sqrt(2)) + tanh(sqrt(7)*Pi/2)*Pi/sqrt(7) - 1/4. - _Amiram Eldar_, Sep 16 2022
%t A290743 Table[(Binomial[n+1,2] - (2-(n - 2 Floor[n/2])) Binomial[Floor[n/2]+1, 2] - (n-2 Floor[n/2]) Binomial[Floor[n/2]+2, 2] + 2), {n, 60}] (* _Vincenzo Librandi_, Oct 04 2017 *)
%o A290743 (PARI) a(n)=(s->my(m=n\s,p=n%s); binomial(n+1,2)-(s-p)*binomial(m+1,2)-p*binomial(m+2,2)+s)(2); \\ _Andrew Howroyd_, Aug 14 2017
%o A290743 (Magma) [Binomial(n+1,2)-(2-(n-2*Floor(n/2)))*Binomial(Floor(n/2)+1,2)-(n-2*Floor(n/2))*Binomial(Floor(n/2)+2,2)+2: n in [1..60]]; // _Vincenzo Librandi_, Oct 04 2017
%Y A290743 Cf. A290744, A290745, A290746, A014206 (bisection), A059100 (bisection).
%K A290743 nonn,easy
%O A290743 1,1
%A A290743 _N. J. A. Sloane_, Aug 11 2017
%E A290743 a(11)-a(55) from _Andrew Howroyd_, Aug 14 2017