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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.

A361826 a(n) is equal to the number of roots of the equation n*cos(x) = sqrt(x).

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%I A361826 #49 May 01 2023 18:06:26
%S A361826 1,1,3,5,7,11,15,21,25,31,39,45,53,63,71,81,91,103,115,127,141,155,
%T A361826 169,183,199,215,233,249,267,287,305,325,347,367,389,413,435,459,485,
%U A361826 509,535,561,589,617,645,673,703,733,765,795,827,861,895,929,963,999,1035
%N A361826 a(n) is equal to the number of roots of the equation n*cos(x) = sqrt(x).
%C A361826 The number of roots of the equation is determined graphically. It is equal to the number of intersection points of two graphs: y = n*cos(x) and y = sqrt(x).
%H A361826 Nicolay Avilov, <a href="/A361826/a361826.jpg">Illustration for a(4)</a>.
%F A361826 Conjecture: a(n) = 2*floor(n^2/(2*Pi)) + 1.
%e A361826 a(4) = 5 because the equation 4*cos(x) = sqrt(x) has 5 roots. See link.
%Y A361826 Cf. A178832.
%K A361826 nonn
%O A361826 1,3
%A A361826 _Nicolay Avilov_, Mar 27 2023