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%I #17 Nov 07 2023 14:35:10
%S 0,0,1,1,0,-1,-1,1,2,1,-1,-2,-1,0,2,2,0,-2,-2,1,2,3,3,2,1,-1,-2,-3,-3,
%T -2,-1,0,3,3,0,-3,-3,2,4,2,-2,-4,-2,1,3,4,4,3,1,-1,-3,-4,-4,-3,-1,0,4,
%U 4,0,-4,-4,2,3,5,5,3,2,-2,-3,-5,-5,-3,-2,1
%N List coordinates (x,y) of the points in an hexagonal grid, sorted first by radial coordinate r and in case of ties, by polar angle 0 <= phi < 2*Pi in a polar coordinate system. Sequence gives the second coordinate in a barycentric coordinate system.
%C Cartesian coordinates (x,y) of the grid points are converted to barycentric coordinates (i,j,k) by i = x - y/sqrt(3), j = 2*y/sqrt(3), k = x + y/sqrt(3). The sequence gives j. i is given in A307014, k is given in A307017.
%H Hugo Pfoertner, <a href="/A307016/b307016.txt">Table of n, a(n) for n = 0..9060</a>, covering range r <= 50.
%H Hugo Pfoertner, <a href="/A307014/a307014.gp.txt">PARI program for A307014 and A307016</a>.
%o (PARI) \\ See Link
%o \\ To create the data of this sequence load program from file and call
%o a307014_16(5, 6) \\ Hugo Pfoertner, Nov 07 2023
%Y Cf. A004016, A035019, A038590, A307014, A307017.
%K sign,look
%O 0,9
%A _Hugo Pfoertner_, Mar 21 2019
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