A351799 Numbers which, when written in French, contain exactly one instance of the letter E.

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

Author

Carole Dubois and Eric Angelini, Feb 19 2022

Keywords

• nonn
• word
• less

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.

Crossrefs

Cf. A006933 ('Eban' numbers), A349887 (exactly one instance in English), A349888 (exactly two instances in English),

Programs

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