A244682 The spiral of Champernowne read by the North-Northwest ray.

1, 1, 6, 7, 1, 8, 2, 2, 5, 4, 5, 8, 8, 9, 0, 1, 7, 2, 5, 1, 2, 3, 2, 2, 5, 7, 9, 3, 6, 3, 8, 4, 5, 2, 8, 5, 2, 4, 0, 6, 7, 9, 3, 7, 0, 6, 7, 9, 1, 6, 0, 0, 6, 2, 4, 1, 2, 0, 9, 4, 3, 4, 1, 9, 1, 5, 6, 7, 0, 4, 7, 8, 9, 2, 3, 0, 0, 7, 6, 7, 2, 3, 2, 2, 8, 5, 5, 2, 9, 5, 8, 8, 8, 8, 7, 1, 1, 1, 9, 6, 4, 4, 9, 1, 1

Offset

1,3

Links

Table of n, a(n) for n=1..105.

Formula

See A244677 formula section.

Example

See A244677 for the spiral of David Gawen Champernowne.

Mathematica

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 - 33n + 18 (* see A244677 formula section *); Array[ almostNatural[ f@#, 10] &, 105]

Crossrefs

Cf. A033307, A033952, A143860, A244677-A244688, A244690-A244692.

Sequence in context: A373020 A280501 A244818 * A201323 A155490 A156918

Adjacent sequences: A244679 A244680 A244681 * A244683 A244684 A244685

Keyword

nonn,easy

Author

Robert G. Wilson v, Jul 04 2014

Status

approved