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a(n) = n represented in bijective base-8 numeration.
3

%I #19 Sep 17 2023 01:35:45

%S 1,2,3,4,5,6,7,8,11,12,13,14,15,16,17,18,21,22,23,24,25,26,27,28,31,

%T 32,33,34,35,36,37,38,41,42,43,44,45,46,47,48,51,52,53,54,55,56,57,58,

%U 61,62,63,64,65,66,67,68,71,72,73,74,75,76,77,78,81,82,83

%N a(n) = n represented in bijective base-8 numeration.

%H Alois P. Heinz, <a href="/A214678/b214678.txt">Table of n, a(n) for n = 1..10000</a>

%H R. R. Forslund, <a href="http://www.emis.de/journals/SWJPAM/Vol1_1995/rrf01.ps">A logical alternative to the existing positional number system</a>, Southwest Journal of Pure and Applied Mathematics, Vol. 1, 1995, 27-29.

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/Zerofree.html">Zerofree</a>

%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Bijective_numeration">Bijective numeration</a>

%p a:= proc(n) local d, l, m; m:= n; l:= NULL;

%p while m>0 do d:= irem(m, 8, 'm');

%p if d=0 then d:=8; m:= m-1 fi;

%p l:= d, l

%p od; parse(cat(l))

%p end:

%p seq(a(n), n=1..100);

%t With[{b = 8}, Flatten@ Table[FromDigits[PadLeft[IntegerDigits[k, b], n] /. k_ :> k + 1], {n, 3}, {k, 0, b^n - 1}] ] (* _Michael De Vlieger_, Sep 16 2023 *)

%Y Column k=8 of A214676.

%K nonn,base,easy

%O 1,2

%A _Alois P. Heinz_, Jul 25 2012