cp's OEIS Frontend

A367812 Lexicographically earliest sequence of distinct nonnegative terms such that the Levenshtein distance (Ld) between a(n) and a(n+1) is equal to 2.

%I A367812 #13 Dec 21 2023 15:17:00
%S A367812 0,11,2,10,3,12,4,13,5,14,6,15,7,16,8,17,9,18,20,1,22,19,21,30,23,31,
%T A367812 24,32,25,33,26,34,27,35,28,36,29,37,40,38,41,39,42,50,43,51,44,52,45,
%U A367812 53,46,54,47,55,48,56,49,57,60,58,61,59,62,70,63,71,64,72,65,73,66,74,67,75,68,76,69,77,80,78
%N A367812 Lexicographically earliest sequence of distinct nonnegative terms such that the Levenshtein distance (Ld) between a(n) and a(n+1) is equal to 2.
%H A367812 Éric Angelini, <a href="https://cinquantesignes.blogspot.com/2023/12/more-levenshtein-distances.html">More Levenshtein distances</a>, Personal blog, December 2023.
%e A367812 a(1) =  0 and a(2) = 11 are separated by an Ld of 2
%e A367812 a(2) = 11 and a(3) =  2 are separated by an Ld of 2
%e A367812 a(3) =  2 and a(4) = 10 are separated by an Ld of 2
%e A367812 a(4) = 10 and a(5) =  3 are separated by an Ld of 2, etc.
%t A367812 a[1]=0;a[n_]:=a[n]=(k=1;While[MemberQ[Array[a,n-1],k]||EditDistance[ToString@a[n-1],ToString@k]!=2,k++];k);Array[a,80]
%o A367812 (Python)
%o A367812 from itertools import islice
%o A367812 from Levenshtein import distance as Ld
%o A367812 def agen(): # generator of terms
%o A367812     an, aset, mink = 0, {0}, 1
%o A367812     while True:
%o A367812         yield an
%o A367812         s, k = str(an), mink
%o A367812         while k in aset or Ld(s, str(k)) != 2: k += 1
%o A367812         an = k
%o A367812         aset.add(k)
%o A367812         while mink in aset: mink += 1
%o A367812 print(list(islice(agen(), 80))) # _Michael S. Branicky_, Dec 01 2023
%Y A367812 Cf. A118763, A367813, A367814, A367815.
%K A367812 base,nonn
%O A367812 1,2
%A A367812 _Eric Angelini_ and _Giorgos Kalogeropoulos_, Dec 01 2023