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A057360
a(n) = floor(3*n/8).
15
0, 0, 0, 1, 1, 1, 2, 2, 3, 3, 3, 4, 4, 4, 5, 5, 6, 6, 6, 7, 7, 7, 8, 8, 9, 9, 9, 10, 10, 10, 11, 11, 12, 12, 12, 13, 13, 13, 14, 14, 15, 15, 15, 16, 16, 16, 17, 17, 18, 18, 18, 19, 19, 19, 20, 20, 21, 21, 21, 22, 22, 22, 23, 23, 24, 24, 24, 25, 25, 25, 26, 26, 27, 27, 27, 28, 28, 28
OFFSET
0,7
COMMENTS
The cyclic pattern (and numerator of the g.f.) is computed using Euclid's algorithm for GCD.
REFERENCES
N. Dershowitz and E. M. Reingold, Calendrical Calculations, Cambridge University Press, 1997.
R. L. Graham, D. E. Knuth and O. Patashnik, Concrete Mathematics, Addison-Wesley, NY, 1994.
LINKS
N. Dershowitz and E. M. Reingold, Calendrical Calculations Web Site.
FORMULA
G.f.: x^3*(1+x^3+x^5) / ( (1+x)*(x^2+1)*(x^4+1)*(x-1)^2 ).
From Wesley Ivan Hurt, May 15 2015: (Start)
a(n) = a(n-1)+a(n-8)-a(n-9).
a(n) = A132292(A008585(n)), n>0.
a(n) = A002265(A032766(n)). (End)
Sum_{n>=3} (-1)^(n+1)/a(n) = Pi/(6*sqrt(3)) + log(3)/2. - Amiram Eldar, Sep 30 2022
MAPLE
A057360:=n->floor(3*n/8): seq(A057360(n), n=0..100); # Wesley Ivan Hurt, May 15 2015
MATHEMATICA
Floor[3 Range[0, 100]/8] (* Wesley Ivan Hurt, May 15 2015 *)
PROG
(Magma) [Floor(3*n/8): n in [0..80]]; // Vincenzo Librandi, Jul 07 2011
(PARI) a(n)=3*n>>3 \\ Charles R Greathouse IV, Jul 07 2011
KEYWORD
nonn,easy
AUTHOR
EXTENSIONS
Numerator of g.f. corrected by R. J. Mathar, Feb 20 2011
STATUS
approved