%I A057365
%S A057365 0,0,1,1,2,3,3,4,4,5,6,6,7,8,8,9,9,10,11,11,12,13,13,14,14,15,16,16,17,
%T A057365 17,18,19,19,20,21,21,22,22,23,24,24,25,26,26,27,27,28,29,29,30,30,31,
%U A057365 32,32,33,34,34,35,35,36,37,37,38,39,39,40,40,41,42,42,43,43,44,45
%N A057365 Floor(13n/21).
%C A057365 The cyclic pattern (and numerator of the gf) is computed using Euclid's 
               algorithm for GCD.
%D A057365 N. Dershowitz and E. M. Reingold, Calendrical Calculations, Cambridge 
               University Press, 1997.
%D A057365 R. L. Graham, D. E. Knuth and O. Patashnik, Concrete Mathematics, Addison-Wesley, 
               NY, 1994.
%H A057365 N. Dershowitz and E. M. Reingold, <a href="http://emr.cs.iit.edu/home/
               reingold/calendar-book/first-edition/">Calendrical Calculations Web 
               Site</a>
%F A057365 G.f.: x^2(1 + x^2 + x^4 + x^5 + x^7 + x^9 + x^10 + x^12 + x^13 + x^15 
               + x^17 + x^18 + x^20)/((1 - x)(1 - x^21)).
%Y A057365 Floors of other ratios: A004526, A002264, A002265, A004523, A057353, 
               A057354, A057355, A057356, A057357, A057358, A057359, A057360, A057361, 
               A057362, A057363, A057364, A057365, A057366, A057367.
%Y A057365 Sequence in context: A073869 A060143 A005206 this_sequence A014245 A096386 
               A135671
%Y A057365 Adjacent sequences: A057362 A057363 A057364 this_sequence A057366 A057367 
               A057368
%K A057365 nonn,easy
%O A057365 0,5
%A A057365 Mitch Harris (Harris.Mitchell(AT)mgh.harvard.edu)