%I #14 Oct 26 2019 03:29:26
%S 1,13,24,35,46,57,68,79,90,2,4,5,6,7,8,9,10,11,12,14,15,16,17,18,19,
%T 20,21,22,23,25,26,27,28,29,30,31,32,33,34,36,37,38,39,40,41,42,43,44,
%U 45,47,48,49,50,51,52,53,54,55,56,58,59,60,61,62,63,64,65,66,67,69,70,71,72,73,74,75,76,77,78,80,81,82,83,84,85,86,87,88,89,91,92,93,94,95,96,97,98,99,100,3
%N a(n) = position of n in the lexicographical ordering A119589 of natural numbers from 1 to 100.
%C Inverse of the permutation A119589. - _M. F. Hasler_, Oct 26 2019
%F a(n) = a(n-1) + a(n-10) - a(n-11) for 21 < n < 100. - _M. F. Hasler_, Sep 03 2018
%F a(n) = k such that A119589(k) = n. - _M. F. Hasler_, Oct 26 2019
%e a(1) = 1
%e a(10) = 2 because "10" comes after "1"
%e a(100) = 3 because "100" comes after "10", but before "11"
%o (PARI) vecsort(vecsort(vector(100,n,Str(n)),,1),,1) \\ _M. F. Hasler_, Sep 03 2018, simplified Oct 25 2019
%Y Cf. A119589 (integers 1..100 in lexicographical order).
%Y Cf. A190016, A190017 (integers 1..10^4 in lexicographical order, and inverse).
%K nonn,base,fini,full
%O 1,2
%A _Dmitry Kamenetsky_, Jun 01 2006, Jun 03 2006
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