|
%I #7 Mar 13 2015 23:52:13
%S 1,1,0,6,0,8,1,3,5,3,4,4,6,1,5,9,9,1,2,6,2,1,7,7,1,2,3,7,6,2,9,6,7,3,
%T 7,6,4,4,6,5,7,5,5,3,6,6,6,1,1,7,7,9,2,8,0,6,9,0,3,5,0,4,1,7,0,2,9,3,
%U 3,6,3,4,4,0,3,5,9,6,8,2,7,4,8,7,1,9,9,0,8,2,1,4,2,9,4,3,9,4,2,7,6,4,7,7,2
%N The hexagonal spiral of Champernowne, read along the 300-degree ray.
%F (12n^2 - 23n + 12)th almost natural number (A033307), Also see formula section of A056105.
%e see A244807 example section for its diagram.
%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_] := 12n^2 - 23n + 12 (* see formula section of A244807 *); Array[ almostNatural[ f@#, 10] &, 105]
%Y Cf. A007376, A244804, A244807, A244808, A244809, A244810, A244811, A244813, A244814, A244815, A244816, A244817, A244818.
%K nonn,easy
%O 1,4
%A _Robert G. Wilson v_, Jul 06 2014
|
