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%I A244809 #11 Mar 13 2015 18:49:30
%S A244809 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,
%T A244809 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,
%U A244809 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
%N A244809 The hexagonal spiral of Champernowne, read along the 30-degree ray.
%F A244809 (3n^2-7n+5)th almost natural number (A033307), Also see formula section of A056105.
%e A244809 See A244807 example section for its diagram.
%t A244809 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]
%Y A244809 Cf. A007376, A056106, A244807, A244808, A244810, A244811, A244812, A244813, A244814, A244815, A244816, A244817, A244818.
%K A244809 nonn,easy
%O A244809 1,2
%A A244809 _Robert G. Wilson v_, Jul 06 2014

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