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%I #13 Nov 13 2018 12:52:44
%S 0,1,2,3,4,5,6,7,8,9,10,11,21,31,41,51,61,71,81,91,20,12,22,32,42,52,
%T 62,72,82,92,30,13,23,33,43,53,63,73,83,93,40,14,24,34,44,54,64,74,84,
%U 94,50,15,25,35,45,55,65,75,85,95,60,16,26,36,46,56,66,76
%N Reverse the nonzero digits of n.
%C This sequence is a self-inverse permutation of nonnegative integers.
%C See A321464 for the ternary variant.
%C This sequence has similarities with A069799: here we reverse nonzero digits, there we reverse nonzero prime exponents.
%H Rémy Sigrist, <a href="/A321474/b321474.txt">Table of n, a(n) for n = 0..10000</a>
%H <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a>
%F a(10 * n) = 10 * a(n).
%F A136400(a(n)) = A136400(n).
%e For n = 1024:
%e - 1024 has 3 nonzero digits: 1, 2 and 4,
%e - so we replace the first nonzero digit by the third, the third by the first (and the second remains in place),
%e - and we obtain a(1024) = 4021.
%o (PARI) a(n, base=10) = my (d=digits(n, base), t=Vecrev(select(sign, d)), i=0); for (j=1, #d, if (d[j], d[j] = t[i++])); fromdigits(d, base)
%Y Cf. A004086, A069799, A136400, A321464.
%K nonn,base
%O 0,3
%A _Rémy Sigrist_, Nov 11 2018