login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A355479
a(n) is the number of distinct honeycomb cell walls built after the n-th step of the walk described in A355478.
4
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 20, 20, 20, 20, 21, 22, 23, 24, 24, 25, 26, 27, 28, 29, 30, 31, 31, 31, 31, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 40, 41, 42, 42, 43, 44, 45, 46, 46, 46, 47, 47, 48, 49, 50, 51, 51, 51
OFFSET
0,3
COMMENTS
See A355478 for more information, animations, and illustration of selected terms.
EXAMPLE
In the following diagrams the walk is shown at the end of the n-th step, together with the position of the bee (*).
.
n 0 1 8 28 60
a(n) 0 1 8 24 47
__
__/ \*_
* __* __ __ / \__/ \__
\ \__ \__/ \__ \__
/ / \__ \__/ \__/ \__
\ \*_ \__ \__/ \__ \__
/ / \ \ / \ \
\ \__/ __/ \__/ __/
/ / __/ / __/
\* \__/ \__/
.
MATHEMATICA
A355479[nmax_]:=Module[{a={0}, w={}, p1={0, 0}, p2, angle=0}, Do[w=Union[w, {Sort[{p1, p2=AngleVector[p1, angle+=If[PrimeQ[n], -1, 1]Pi/3]}]}]; p1=p2; AppendTo[a, Length[w]], {n, nmax}]; a];
A355479[100] (* Paolo Xausa, Jan 05 2023 *)
CROSSREFS
KEYWORD
nonn,walk
AUTHOR
Paolo Xausa, Jul 18 2022
STATUS
approved