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A298359 Lexicographically earliest sequence of distinct positive terms such that, for any n > 0, Sum_{k = 1..n} 10^(k-1) * a(k) can be computed without carry in decimal base.

%I A298359 #14 Jan 22 2018 03:05:27
%S A298359 1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,20,21,22,23,24,25,26,27,
%T A298359 30,31,32,33,34,35,36,40,41,42,43,44,45,50,51,52,53,54,60,61,62,63,70,
%U A298359 71,72,80,81,90,100,19,37,46,55,64,73,82,91,110,28,56,74
%N A298359 Lexicographically earliest sequence of distinct positive terms such that, for any n > 0, Sum_{k = 1..n} 10^(k-1) * a(k) can be computed without carry in decimal base.
%C A298359 More informally: write the terms in decimal under each other, right-justified; the digits on each diagonal in downwards direction sum at most to 9.
%C A298359 The corresponding sequence for base 2 is A094958.
%C A298359 See also A298425 for a similar sequence.
%H A298359 Rémy Sigrist, <a href="/A298359/b298359.txt">Table of n, a(n) for n = 1..10000</a>
%H A298359 Rémy Sigrist, <a href="/A298359/a298359.gp.txt">PARI program for A298359</a>
%e A298359 The first terms, alongside 10^(n-1) * a(n), are:
%e A298359   n   a(n)  10^(n-1) * a(n)
%e A298359   --  ----  -------------------
%e A298359    1   1                      1
%e A298359    2   2                     20
%e A298359    3   3                    300
%e A298359    4   4                   4000
%e A298359    5   5                  50000
%e A298359    6   6                 600000
%e A298359    7   7                7000000
%e A298359    8   8               80000000
%e A298359    9   9              900000000
%e A298359   10  10            10000000000
%e A298359   11  11           110000000000
%e A298359   12  12          1200000000000
%e A298359   13  13         13000000000000
%e A298359   14  14        140000000000000
%e A298359   15  15       1500000000000000
%e A298359   16  16      16000000000000000
%e A298359   17  17     170000000000000000
%e A298359   18  18    1800000000000000000
%e A298359   19  20   20000000000000000000
%e A298359   20  21  210000000000000000000
%e A298359 The terms on the third column can be summed without carry in decimal base.
%o A298359 (PARI) See Links section.
%Y A298359 Cf. A094958, A298425.
%K A298359 nonn,base
%O A298359 1,2
%A A298359 _Rémy Sigrist_, Jan 17 2018