%I #6 Jul 05 2014 17:00:47
%S 1,1,4,7,1,6,2,9,7,4,6,7,7,2,0,6,9,1,5,0,2,2,1,7,3,2,9,7,2,3,8,9,9,4,
%T 8,5,4,5,0,3,7,6,3,4,8,8,7,7,7,9,0,4,3,1,1,1,3,4,2,1,3,2,5,4,1,5,1,6,
%U 6,1,7,0,7,9,1,0,9,8,1,2,2,8,9,4,2,5,7,0,6,2,8,6,1,9,3,1,5,2,2,3,4,4,3,6,3
%N The spiral of Champernowne read by the North-Northeast ray.
%F See A244677 formula section.
%e See A244677 for the spiral of David Gawen Champernowne.
%t almostNatural[n_, b_] := Block[{m = 0, d = n, i = 1, l, p}, While[m <= d, l = m; m = (b - 1) i*b^(i - 1) + l; i++]; i--; p = Mod[d - l, i]; q = Floor[(d - l)/i] + b^(i - 1); If[p != 0, IntegerDigits[q, b][[p]], Mod[q - 1, b]]]; f[n_] := 16n^2 - 35n + 20 (* see A244677 formula section *); Array[ almostNatural[ f@#, 10] &, 105]
%Y Cf. A033307, A033952, A143861, A244677 - A244688, A244690 - A244692.
%K nonn,easy
%O 1,3
%A _Robert G. Wilson v_, Jul 04 2014
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