%I #22 Oct 30 2022 18:19:59
%S 1,4,2,35,33,3,5,16,14,12,10,8,6,188,58,186,184,23,25,7,9,11,13,15,17,
%T 182,48,46,50,1774,1770,1772,1786,1784,1766,40,1764,32,34,36,22,20,18,
%U 24,26,204,202,200,198,196,194,192,190,1758,1762,1760,79,77,1782,602
%N Term in A064389 (variation (4) of Recamán's sequence) where n appears, or 0 if n never appears.
%C Is it ever 0?
%C If all a(n)>0, then this is the inverse permutation of A064389. - _M. F. Hasler_, Nov 03 2014
%C After 10^12 terms of A064389, the first unknown term of this sequence is 5191516. - _Benjamin Chaffin_, Oct 09 2016
%H Benjamin Chaffin, <a href="/A078758/b078758.txt">Table of n, a(n) for n = 1..20000</a> [First 6655 terms from Nick Hobson]
%H Nick Hobson, <a href="/A078758/a078758.py.txt">Python program for this sequence</a>
%H <a href="/index/Rea#Recaman">Index entries for sequences related to Recamán's sequence</a>
%H <a href="/index/Per#IntegerPermutation">Index entries for sequences that are permutations of the natural numbers</a>
%o (PARI) for(i=1,9e9,for(j=1,#a064389,a064389[j]==i&&print1(j",")+next(2));break) \\ The terms of A064389 must be stored in the vector a064389. - _M. F. Hasler_, Nov 03 2014
%Y Cf. A064389, A005132, A057167.
%K nonn
%O 1,2
%A _Reiner Martin_, Jan 08 2003