%I #12 Jun 30 2019 01:53:19

%S 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,1,3,3,3,

%T 3,3,3,3,3,3,3,3,3,3,3,2,1,4,4,4,4,4,4,4,4,4,4,4,4,4,3,2,1,5,5,5,5,5,

%U 5,5,5,5,5,5,5,4,3,2,1,6,6,6,6,6,6,6

%N n is the a(n)-th positive integer having its digitsum in base-16 representation.

%C Ordinal transform of A053836. - _Alois P. Heinz_, Dec 23 2018

%H Reinhard Zumkeller, <a href="/A263110/b263110.txt">Table of n, a(n) for n = 1..10000</a>

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

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

%H Wikipedia, <a href="http://en.wikipedia.org/wiki/Hexadecimal">Hexadecimal</a>

%H Wikipedia, <a href="http://en.wikipedia.org/wiki/Digit_sum">Digit sum</a>

%o (Haskell)

%o import Data.IntMap (empty, findWithDefault, insert)

%o a263110 n = a263110_list !! (n-1)

%o a263110_list = f 1 empty where

%o f x m = y : f (x + 1) (insert q (y + 1) m) where

%o y = findWithDefault 1 q m; q = a053836 x

%Y Cf. A053836, A254524, A263017, A263109.

%K nonn,base

%O 1,16

%A _Reinhard Zumkeller_, Oct 09 2015