A358211 Self-locating strings within e: numbers k such that the string k is at position k (after the decimal point) in the decimal digits of e, where 7 is the 0th digit.

1, 8, 215, 374, 614, 849, 4142, 7945, 5964055, 8008913, 7131377227, 8829981707

Offset

0,2

Links

Table of n, a(n) for n=0..11.

Example

The first two terms 1 and 8 are depicted here:
Position:      0123456789...
Digits of e: 2.7182818284...
               .^......^....
1 is the first term because 1 is in position 1 after the decimal point (when starting to count with 0).
8 is the second term because 8 is in position 8 etc.

Prog

(Python)
# after Michael S. Branicky in A064810
# First get a file with e digits, e.g. https://www4.baumann.at/downloads/e.txt
with open('e.txt', 'r') as f: digits_of_e = f.readline()[2:]
def afind():
  global digits_of_e
  for k in range(len(digits_of_e)):
    s = str(k)
    if digits_of_e[k:k+len(s)] == s: print(k, end=", ")
afind()

Crossrefs

Cf. A001113, A064810, A205648.

Sequence in context: A024288 A081794 A221042 * A247032 A027646 A224096

Adjacent sequences: A358208 A358209 A358210 * A358212 A358213 A358214

Keyword

base,nonn,more

Author

Chris Baumann, Nov 04 2022

Extensions

a(9)-a(12) from Michael S. Branicky, Nov 04 2022

Status

approved