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A047252
Numbers that are congruent to {0, 1, 3, 4, 5} mod 6.
3
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
1,3
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
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 *)
CROSSREFS
Cf. A047263.
Sequence in context: A184336 A183300 A155854 * A039235 A247782 A039179
KEYWORD
nonn
STATUS
approved