A349888 - OEIS

A349888

Numbers which, when written in English, contain exactly two instances of the letter E.

3, 7, 12, 13, 14, 15, 16, 21, 25, 28, 29, 33, 37, 43, 47, 53, 57, 63, 67, 70, 72, 74, 76, 81, 85, 88, 89, 91, 95, 98, 99, 100, 102, 104, 106, 130, 132, 134, 136, 140, 142, 144, 146, 150, 152, 154, 156, 160, 162, 164, 166, 201, 205, 208, 209, 210, 220, 222, 224, 226, 231, 235, 238, 239

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,1

LINKS

Michael S. Branicky, Table of n, a(n) for n = 1..10000

EXAMPLE

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.

PROG

(Python)

from num2words import num2words

def ok(n): return num2words(n).count("e") == 2

print([k for k in range(311) if ok(k)]) # Michael S. Branicky, Feb 19 2022