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 A006969 M4334 #45 Aug 14 2021 15:11:04
%S A006969 7,8,9,9,9,7,8,8,8,7,7,8,9,11,9,8,12,12,12,9,15,14,15,15,15,13,14,14,
%T A006969 14,9,16,15,16,16,16,14,15,15,15,11,18,17,18,18,18,16,17,17,17,12,19,
%U A006969 18
%N A006969 Number of characters in French ordinal numbers.
%C A006969 Nombres de caractères (lettres, espaces et tirets) des nombres ordinaux en français.
%C A006969 In contrast to A196278, hyphens and spaces are counted here. First differs at n = 17 (dix-septième). - _Georg Fischer_, Aug 07 2021
%C A006969 In French the final -s in "quatre-vingts", "deux cents", ... disappears when the ordinal suffix "-ième" is appended. (This is currently incorrectly handled in the Python module num2words.) Also, the trailing "-e" of numbers ending in "quatre", "onze" - "seize", "trente" - "soixante" disappears. Therefore, in all these cases the name of the ordinal has only 3 letters more than the name of the cardinal, viz. a(n) = A007005(n)+3. For numbers ending in "cinq", there appears an additional "u", whence a(n) = A007005(n)+5 in this case. - _M. F. Hasler_, Aug 08 2021
%D A006969 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%H A006969 <a href="/index/Lc#letters">Index entries for sequences related to number of letters in n</a>
%F A006969 a(n) = A007005(n) + e, where e = 4 except for n = 1 and when the French name of n ends in "cinq" (then e = 5), or when it ends in "-e" or "-ts" (then e = 3). - _M. F. Hasler_, Aug 08 2021
%e A006969 a(21) = # "vingt-et-unième" = 15, where # means length of the string.
%e A006969 a(50) = # "cinquantième" = 12.
%e A006969 a(80) = # "quatre-vingtième": the '-s' disappears from "quatre-vingts".
%e A006969 a(200) = # "deux-centième": the '-s' disappears from "deux cents".
%o A006969 (PARI) apply( {A006969(n, t=French(n))=#t+if(n==1||"nq"==t=Strchr(Vecsmall(t)[-2..-1]), 5, "ts"==t || Vec(t)[2]=="e", 3, 4)}, [1..55]) \\ See A007005 for French(). - _M. F. Hasler_, Aug 08 2021
%Y A006969 Cf. A006944 (in American English), A196278 (similar, but not counting spaces and hyphens).
%Y A006969 Cf. A007005, A167507 (number of letters/characters in French name of n).
%K A006969 nonn,word
%O A006969 1,1
%A A006969 _N. J. A. Sloane_, _Simon Plouffe_
%E A006969 Edited by _M. F. Hasler_, Aug 08 2021