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A263109 n is the a(n)-th positive integer having its digitsum in base-12 representation.

%I A263109 #19 Feb 16 2025 08:33:27
%S A263109 1,1,1,1,1,1,1,1,1,1,1,2,2,2,2,2,2,2,2,2,2,2,1,3,3,3,3,3,3,3,3,3,3,2,
%T A263109 1,4,4,4,4,4,4,4,4,4,3,2,1,5,5,5,5,5,5,5,5,4,3,2,1,6,6,6,6,6,6,6,5,4,
%U A263109 3,2,1,7,7,7,7,7,7,6,5,4,3,2,1,8,8,8
%N A263109 n is the a(n)-th positive integer having its digitsum in base-12 representation.
%C A263109 Ordinal transform of A053832. - _Alois P. Heinz_, Dec 23 2018
%H A263109 Reinhard Zumkeller, <a href="/A263109/b263109.txt">Table of n, a(n) for n = 1..10000</a>
%H A263109 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/Duodecimal.html">Duodecimal</a>
%H A263109 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/DigitSum.html">Digit Sum</a>
%H A263109 Wikipedia, <a href="http://en.wikipedia.org/wiki/Duodecimal">Duodecimal</a>
%H A263109 Wikipedia, <a href="http://en.wikipedia.org/wiki/Digit_sum">Digit sum</a>
%t A263109 b[_] = 1;
%t A263109 a[n_] := a[n] = With[{t = Total[IntegerDigits[n, 12]]}, b[t]++];
%t A263109 Array[a, 100] (* _Jean-François Alcover_, Dec 18 2021 *)
%o A263109 (Haskell)
%o A263109 import Data.IntMap (empty, findWithDefault, insert)
%o A263109 a263109 n = a263109_list !! (n-1)
%o A263109 a263109_list = f 1 empty where
%o A263109    f x m = y : f (x + 1) (insert q (y + 1) m) where
%o A263109            y = findWithDefault 1 q m; q = a053832 x
%Y A263109 Cf. A053832, A254524, A263017, A263110.
%K A263109 nonn,base
%O A263109 1,12
%A A263109 _Reinhard Zumkeller_, Oct 09 2015