login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A244809 The hexagonal spiral of Champernowne, read along the 30-degree ray. 11
1, 3, 0, 7, 7, 0, 6, 5, 7, 1, 3, 5, 1, 1, 2, 2, 7, 2, 3, 1, 3, 4, 3, 5, 6, 3, 0, 7, 1, 6, 9, 7, 7, 0, 1, 7, 0, 2, 3, 8, 7, 5, 5, 3, 8, 7, 8, 2, 3, 0, 1, 5, 2, 3, 4, 2, 5, 7, 7, 3, 2, 0, 1, 8, 3, 4, 5, 7, 8, 8, 9, 0, 7, 2, 3, 7, 0, 7, 8, 8, 7, 1, 3, 3, 8, 6, 8, 2, 3, 1, 3, 5, 2, 7, 8, 2, 5, 3, 4, 3, 2, 9, 0, 8, 3 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

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

FORMULA

(3n^2-7n+5)th almost natural number (A033307), Also see formula section of A056105.

EXAMPLE

See A244807 example section for its diagram.

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_] := 3n^2- 7n+ 5 (* see formula section of A244807 *); Array[ almostNatural[ f@#, 10] &, 105]

CROSSREFS

Cf. A007376, A056106, A244807, A244808, A244810, A244811, A244812, A244813, A244814, A244815, A244816, A244817, A244818.

Sequence in context: A011200 A201573 A021329 * A316554 A201900 A344387

Adjacent sequences:  A244806 A244807 A244808 * A244810 A244811 A244812

KEYWORD

nonn,easy

AUTHOR

Robert G. Wilson v, Jul 06 2014

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified May 24 18:49 EDT 2022. Contains 354043 sequences. (Running on oeis4.)