A047252 Numbers that are congruent to {0, 1, 3, 4, 5} mod 6.

0, 1, 3, 4, 5, 6, 7, 9, 10, 11, 12, 13, 15, 16, 17, 18, 19, 21, 22, 23, 24, 25, 27, 28, 29, 30, 31, 33, 34, 35, 36, 37, 39, 40, 41, 42, 43, 45, 46, 47, 48, 49, 51, 52, 53, 54, 55, 57, 58, 59, 60, 61, 63, 64, 65, 66, 67, 69, 70, 71, 72, 73, 75, 76, 77, 78, 79

Offset: 1

Author

N. J. A. Sloane

Keywords

• nonn

Links

• Index entries for linear recurrences with constant coefficients, signature (1,0,0,0,1,-1).

Crossrefs

Cf. A047263.

Programs

Maple

seq(floor((6*n-3)/5), n= 1..70); # Gary Detlefs, Mar 07 2010

Mathematica

Flatten[#+{0,1,3,4,5}&/@(6Range[0,12])]  (* Harvey P. Dale, Apr 21 2011 *)

Formula

a(n) = floor((6n-3)/5). - Gary Detlefs, Mar 07 2010

G.f.: x^2*(1+x)*(x^3+x+1) / ( (x^4+x^3+x^2+x+1)*(x-1)^2 ). - R. J. Mathar, Oct 08 2011

Sum_{n>=2} (-1)^n/a(n) = log(2+sqrt(3))/sqrt(3) - (3-2*sqrt(3))*Pi/36. - Amiram Eldar, Dec 17 2021