cp's OEIS Frontend

A244691 The spiral of Champernowne read by the Southeast ray.

%I A244691 #6 Jul 05 2014 17:08:05
%S A244691 1,9,7,9,5,5,9,1,1,1,3,2,2,9,3,3,9,4,4,3,5,6,1,7,8,3,9,3,9,7,7,9,3,9,
%T A244691 7,7,9,3,9,7,7,9,3,9,7,7,9,3,9,7,7,9,3,9,7,7,9,3,9,7,7,9,3,9,7,7,9,3,
%U A244691 9,7,7,9,3,9,7,7,9,3,9,7,7,9,3,9,7,7,9,3,9,7,7,9,3,9,7,7,9,3,9,0,0,3,1,1,0
%N A244691 The spiral of Champernowne read by the Southeast ray.
%F A244691 See A244677 formula section.
%e A244691 See A244677 for the spiral of David Gawen Champernowne.
%t A244691 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 - 4n + 1 (* see A244677 formula section *); Array[ almostNatural[ f@#, 10] &, 105]
%Y A244691 Cf. A033307, A016754, A033952, A244677-A244688, A244690, A244692.
%K A244691 nonn,easy
%O A244691 1,2
%A A244691 _Robert G. Wilson v_, Jul 04 2014