|
%I #9 Feb 19 2022 10:36:21
%S 3,7,12,13,14,15,16,21,25,28,29,33,37,43,47,53,57,63,67,70,72,74,76,
%T 81,85,88,89,91,95,98,99,100,102,104,106,130,132,134,136,140,142,144,
%U 146,150,152,154,156,160,162,164,166,201,205,208,209,210,220,222,224,226,231,235,238,239
%N Numbers which, when written in English, contain exactly two instances of the letter E.
%H Michael S. Branicky, <a href="/A349888/b349888.txt">Table of n, a(n) for n = 1..10000</a>
%e THREE has two Es (and is thus in the sequence), FOUR has no E, FIVE has only one, SIX has none, SEVEN has two Es (and is thus in the sequence). Etc.
%o (Python)
%o from num2words import num2words
%o def ok(n): return num2words(n).count("e") == 2
%o print([k for k in range(311) if ok(k)]) # _Michael S. Branicky_, Feb 19 2022
%Y Cf. A006933 ('Eban' numbers) and A349887 (exactly one instance).
%K word,nonn
%O 1,1
%A _Eric Angelini_, Dec 04 2021
%E a(7) = 16 inserted by _Michael S. Branicky_, Feb 19 2022
|
