This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A351799 #7 Feb 19 2022 10:37:41
%S A351799 0,2,4,7,9,11,12,14,15,17,19,21,22,24,27,29,40,43,45,46,48,50,53,55,
%T A351799 56,58,60,63,65,66,68,70,78,80,81,83,85,86,88,90,98,100,101,103,105,
%U A351799 106,108,110,118,120,123,125,126,128,300,301,303,305,306,308,310
%N A351799 Numbers which, when written in French, contain exactly one instance of the letter E.
%C A351799 ZERO(0) has one E (and is thus in the sequence), UN(1) has no E, DEUX(2) has one, TROIS(3) has none, QUATRE(4) has one E (and is thus in the sequence). etc.
%o A351799 (Python)
%o A351799 from num2words import num2words
%o A351799 from unidecode import unidecode
%o A351799 def ok(n): return unidecode(num2words(n, lang='fr')).count("e") == 1
%o A351799 print([k for k in range(311) if ok(k)]) # _Michael S. Branicky_, Feb 19 2022
%Y A351799 Cf. A006933 ('Eban' numbers), A349887 (exactly one instance in English), A349888 (exactly two instances in English),
%K A351799 nonn,word,less
%O A351799 1,2
%A A351799 _Carole Dubois_ and _Eric Angelini_, Feb 19 2022