A229190 Beginning position of n in the decimal expansion of the Copeland-Erdos constant.

48, 5, 1, 2, 21, 3, 31, 4, 41, 12, 47, 5, 62, 7, 22, 77, 32, 9, 95, 11, 589, 110, 113, 1, 128, 131, 137, 63, 149, 15, 158, 8, 14, 123, 24, 2, 188, 19, 42, 72, 206, 21, 215, 23, 227, 233, 236, 25, 248, 75, 257, 78

Offset: 0

Author

Eric W. Weisstein, Sep 15 2013

Keywords

• nonn
• base
• less

Comments

Same as A165449 but including the a(0) term.

Links

• Eric W. Weisstein, Table of n, a(n) for n = 0..999
• Eric Weisstein's World of Mathematics, Copeland-Erdos Constant Digits
• Eric Weisstein's World of Mathematics, Constant Digit Scanning

Crossrefs

Cf. A033308 (decimal expansion of the Copeland-Erdos constant).

Cf. A165449 (same sequence but omitting the a(0) term).

Programs

Python

from sympy import primerange
from itertools import count, takewhile
def afind(plimit):
  s = "".join(str(p) for p in primerange(1, plimit+1))
  return [1+s.find(str(n)) for n in takewhile(lambda i: str(i) in s, count(0))]
print(afind(10**4)) # Michael S. Branicky, May 01 2021