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.
%I A057359 #22 Sep 30 2022 07:47:41
%S A057359 0,0,1,2,2,3,4,5,5,6,7,7,8,9,10,10,11,12,12,13,14,15,15,16,17,17,18,
%T A057359 19,20,20,21,22,22,23,24,25,25,26,27,27,28,29,30,30,31,32,32,33,34,35,
%U A057359 35,36,37,37,38,39,40,40,41,42,42,43,44,45,45,46,47,47,48,49,50,50,51
%N A057359 a(n) = floor(5*n/7).
%C A057359 The cyclic pattern (and numerator of the gf) is computed using Euclid's algorithm for GCD.
%D A057359 N. Dershowitz and E. M. Reingold, Calendrical Calculations, Cambridge University Press, 1997.
%D A057359 R. L. Graham, D. E. Knuth and O. Patashnik, Concrete Mathematics, Addison-Wesley, NY, 1994.
%H A057359 G. C. Greubel, <a href="/A057359/b057359.txt">Table of n, a(n) for n = 0..5000</a>
%H A057359 N. Dershowitz and E. M. Reingold, <a href="http://emr.cs.iit.edu/home/reingold/calendar-book/first-edition/">Calendrical Calculations Web Site</a>.
%H A057359 <a href="/index/Rec#order_08">Index entries for linear recurrences with constant coefficients</a>, signature (1,0,0,0,0,0,1,-1).
%F A057359 G.f. x^2*(1+x+x^3+x^4+x^5) / ( (x^6+x^5+x^4+x^3+x^2+x+1)*(x-1)^2 ). Numerator corrected Feb 20 2011
%F A057359 Sum_{n>=2} (-1)^n/a(n) = sqrt(10-2*sqrt(5))*Pi/10 + log(phi)/sqrt(5) - log(2)/5, where phi is the golden ratio (A001622). - _Amiram Eldar_, Sep 30 2022
%t A057359 Floor[5 Range[0,75]/7] (* _Harvey P. Dale_, Mar 18 2011 *)
%o A057359 (PARI) a(n)=5*n\7 \\ _Charles R Greathouse IV_, Sep 02 2015
%o A057359 (Magma) [Floor(5*n/7): n in [0..50]]; // _G. C. Greubel_, Nov 02 2017
%Y A057359 Floors of other ratios: A004526, A002264, A002265, A004523, A057353, A057354, A057355, A057356, A057357, A057358, A057359, A057360, A057361, A057362, A057363, A057364, A057365, A057366, A057367.
%Y A057359 Cf. A001622.
%K A057359 nonn,easy
%O A057359 0,4
%A A057359 _Mitch Harris_