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%I #17 Nov 01 2022 03:11:52
%S 0,0,1,0,0,1,4,2,3,2,0,1,0,0,1,0,0,1,4,2,3,6,12,9,12,10,7,8,6,7,10,8,
%T 9,8,6,7,6,4,1,2,0,1,2,2,3,2,0,1,0,0,1,0,0,1,4,2,3,2,0,1,0,0,1,0,0,1,
%U 4,2,3,6,12,9,12,10,7,8,6,7,10,8,9,12,18
%N a(n) is the Y-coordinate of the n-th point of the Kochawave curve; sequence A335380 gives X-coordinates.
%C Coordinates are given on a hexagonal lattice with X-axis and Y-axis as follows:
%C Y
%C /
%C /
%C 0 ---- X
%H Rémy Sigrist, <a href="/A335381/b335381.txt">Table of n, a(n) for n = 0..4096</a>
%H Rémy Sigrist, <a href="https://arxiv.org/abs/2210.17320">The Kochawave curve, a variant of the Koch curve</a>, arXiv:2210.17320 [math.HO], 2022.
%H Rémy Sigrist, <a href="/A335381/a335381.gp.txt">PARI program for A335381</a>
%H <a href="/index/Con#coordinates_2D_curves">Index entries for sequences related to coordinates of 2D curves</a>
%F a(4^k) = 0 for any k >= 0.
%e The Kochawave curve starts (on a hexagonal lattice) as follows:
%e . . . . . . + . . .
%e /|6
%e / |
%e / |
%e . . . . . . | . .+ . .
%e / | .../ 8
%e / | ... /
%e / | ... /
%e . . . . . . +. + . .
%e / 7 |9
%e / |
%e / |
%e . . .+ . .+ . +11 | . .+ .
%e .../ 2 ... 5 / \ | .../ 14
%e ... / ... / \ | ... /
%e ... / ... / \| ... /
%e +-------+. +-------+. . . +-------+. +-------+
%e 0 1 3 4 12 13 10 15 16
%e - hence a(2) = a(5) = a(11) = a(14) = 1.
%o (PARI) See Links section.
%Y Cf. A335380.
%K nonn
%O 0,7
%A _Rémy Sigrist_, Jun 04 2020