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A351799
Numbers which, when written in French, contain exactly one instance of the letter E.
0
0, 2, 4, 7, 9, 11, 12, 14, 15, 17, 19, 21, 22, 24, 27, 29, 40, 43, 45, 46, 48, 50, 53, 55, 56, 58, 60, 63, 65, 66, 68, 70, 78, 80, 81, 83, 85, 86, 88, 90, 98, 100, 101, 103, 105, 106, 108, 110, 118, 120, 123, 125, 126, 128, 300, 301, 303, 305, 306, 308, 310
OFFSET
1,2
COMMENTS
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.
PROG
(Python)
from num2words import num2words
from unidecode import unidecode
def ok(n): return unidecode(num2words(n, lang='fr')).count("e") == 1
print([k for k in range(311) if ok(k)]) # Michael S. Branicky, Feb 19 2022
CROSSREFS
Cf. A006933 ('Eban' numbers), A349887 (exactly one instance in English), A349888 (exactly two instances in English),
Sequence in context: A308496 A226812 A185978 * A120749 A187978 A190193
KEYWORD
nonn,word,less
AUTHOR
Carole Dubois and Eric Angelini, Feb 19 2022
STATUS
approved