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%I #9 Oct 27 2014 09:36:19
%S 0,7,1,8,2,9,3,10,4,11,12,15,16,19,20,23,24,27,28,31,5,6,13,14,17,18,
%T 21,22,25,26,32,35,36,39,40,43,44,47,48,51,29,30,33,34,37,38,41,42,45,
%U 46,52,55,56,59,60,63,64,67,68,71,49,50,53,54,57,58,61,62,65,66,72,75,76
%N Inverse permutation of A249278 (such that first digit of a(n+1) has parity of a(n)).
%H Reinhard Zumkeller, <a href="/A249279/b249279.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>
%o (PARI) N=100;vector(N,n,t=0;for(i=1,#A249278,A249278[i]==n-1&&(t=i)&&break);t-1)
%o (Haskell)
%o import Data.List (elemIndex); import Data.Maybe (fromJust)
%o a249279 = fromJust . (`elemIndex` a249278_list)
%o -- _Reinhard Zumkeller_, Oct 27 2014
%K nonn
%O 0,2
%A _M. F. Hasler_, Oct 24 2014