A019271 A self-descriptive sequence: positions of consonants in "zero, two, four, ...".

0, 2, 4, 5, 7, 10, 11, 13, 15, 17, 19, 20, 22, 24, 26, 28, 29, 30, 32, 33, 36, 37, 39, 40, 43, 44, 46, 48, 49, 52, 53, 55, 57, 60, 61, 62, 64, 65, 66, 67, 68, 70, 71, 72, 73, 74, 76, 77, 79, 80, 81, 82, 85, 86, 87, 89, 90, 91, 92, 94, 95, 96, 98, 99, 100, 103, 104, 105, 106, 107

Offset

0,2

Links

Table of n, a(n) for n=0..69.

Sean A. Irvine, Java program (github)

Prog

(Python)
from itertools import islice
from num2words import num2words
def n2w(n): return "".join(c for c in num2words(n).replace(" and", "") if c.isalpha())
def agen():
    k, s = 0, "zero"
    while True:
        t = ""
        for c in s:
            if c not in "aeiou":
                yield k
                if k: t += n2w(k)
            k += 1
        s = t
print(list(islice(agen(), 70))) # Michael S. Branicky, May 17 2026

Crossrefs

Sequence in context: A024914 A189636 A117741 * A050130 A039672 A014370

Adjacent sequences: A019268 A019269 A019270 * A019272 A019273 A019274

Keyword

word,nonn

Author

Chris Cole (chris(AT)questrel.com)

Extensions

a(38) onwards corrected by Sean A. Irvine, Mar 04 2019

Status

approved