A068988 a(n) = first position in the decimal expansion of e where the pattern "1,2,...,n" occurs.

3, 371, 604, 1004, 166413, 420753

Offset

1,1

Comments

1. We may never know if a(n) is defined for all n.

2. We split up the digits of any number > 9 in the pattern, e.g., if n = 11, we search for the pattern "1,2,3,4,5,6,7,8,9,1,0,1,1".

3. The pattern "1,2,3,4,5" does not occur before the 100,000th term in the digit sequence of e.

It appears that a(7) > 5000000. - Rick L. Shepherd, Aug 21 2002

Links

Table of n, a(n) for n=1..6.

R. Nemiroff and J. Bonnell, The first 5 million digits of the number e

Mathematica

p = ToString[N[E, 100000]/10]; t = {1, 12, 123, 1234}; g[n_] := StringPosition[p, ToString[n]][[1]][[1]] - 2; Table[g[t[[i]]], {i, 1, 4}]

Crossrefs

Cf. A001113 (e, with several sources of digits).

Sequence in context: A324269 A173648 A110717 * A136025 A370448 A157577

Adjacent sequences: A068985 A068986 A068987 * A068989 A068990 A068991

Keyword

nonn,base

Author

Joseph L. Pe, Apr 01 2002

Extensions

More terms from Rick L. Shepherd, Aug 21 2002

Status

approved