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The spiral of Champernowne read by the Northeast ray.
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%I #6 Jul 05 2014 16:58:42

%S 1,3,1,0,3,0,1,6,1,1,3,1,2,3,2,3,7,4,4,5,5,6,7,7,7,3,9,9,7,1,2,2,5,3,

%T 6,4,5,6,2,7,7,9,0,1,1,2,0,4,7,6,2,8,5,0,6,2,5,4,2,7,7,9,0,2,1,4,0,7,

%U 7,0,2,2,5,5,6,8,5,1,2,4,7,7,0,1,1,4,0,8,7,1,2,5,5,8,6,2,5,6,2,0,0,4,0,0,8

%N The spiral of Champernowne read by the 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_] := 4n^2 - 10n + 7 (* see A244677 formula section *); Array[ almostNatural[ f@#, 10] &, 105]

%Y Cf. A033307, A054554, A244677 - A244688, A033952, A244690 - A244692.

%K nonn,easy

%O 1,2

%A _Robert G. Wilson v_, Jul 04 2014