cp's OEIS Frontend

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.

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A300076 A sequence based on the period 6 sequence A300075.

Original entry on oeis.org

0, 1, 1, 2, 2, 2, 3, 4, 4, 5, 5, 5, 6, 7, 7, 8, 8, 8, 9, 10, 10, 11, 11, 11, 12, 13, 13, 14, 14, 14, 15, 16, 16, 17, 17, 17, 18, 19, 19, 20, 20, 20, 21, 22, 22, 23, 23, 23, 24, 25, 25, 26, 26, 26, 27, 28, 28, 29, 29, 29, 30, 31, 31, 32, 32, 32, 33, 34, 34, 35, 35, 35, 36, 37, 37, 38, 38, 38, 39, 40, 40, 41, 41, 41, 42, 43, 43, 44, 44, 44
Offset: 0

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Author

Wolfdieter Lang, Mar 03 2018

Keywords

Comments

If 1 is added to each entry and the offset is set to 1 then the resulting sequence can be used to obtain integers in the quadratic number field Q(sqrt(3)) for the two components of the vertices V0_{-k}, as well as V3_{-k}, for k >= 1, of a k-family of ascending regular hexagons. Their centers 0{-k} form part of a discrete hexagon spiral.

Crossrefs

Formula

a(n) = A300075(n) + 3*floor(n/6), n >= 0.
a(n) = A300293(n-1) + 1, n >= 1.
G.f.: x*(1 + x^2 + x^5)/((1 - x^6)*(1 - x)) = G(x) + 3*x^6/((1-x)*(1-x^6)), with the g.f. G(x) of A300075.

A300290 Period 6: repeat [0, 1, 2, 2, 3, 3].

Original entry on oeis.org

0, 1, 2, 2, 3, 3, 0, 1, 2, 2, 3, 3, 0, 1, 2, 2, 3, 3, 0, 1, 2, 2, 3, 3, 0, 1, 2, 2, 3, 3, 0, 1, 2, 2, 3, 3, 0, 1, 2, 2, 3, 3, 0, 1, 2, 2, 3, 3, 0, 1, 2, 2, 3, 3, 0, 1, 2, 2, 3, 3, 0, 1, 2, 2, 3, 3, 0, 1, 2, 2, 3, 3, 0, 1, 2, 2, 3, 3, 0, 1, 2, 2, 3, 3, 0, 1, 2, 2, 3, 3
Offset: 0

Views

Author

Wolfdieter Lang, Mar 03 2018

Keywords

Comments

Underlying A300068(n+2), n >= 0.

Crossrefs

Formula

a(n) = n (mod 6) - floor((n (mod 6))/3) - floor((n (mod 6))/5), n >= 0.
G.f.: x*(1 + x*(2 + 3*x^2)*(1 + x))/(1 - x^6).
a(n) = (11 - 5*cos(n*Pi/3) - 5*cos(2*n*Pi/3) - cos(n*Pi) - 3*sqrt(3)*sin(n*Pi/3) - sqrt(3)*sin(2*n*Pi/3))/6. - Wesley Ivan Hurt, Oct 04 2018
Showing 1-2 of 2 results.