A166028 a(n) is the starting position of the second occurrence of a string of the initial n decimal digits of e in the decimal expansion of e.

4, 62, 918, 5503, 29169, 252474, 7910575, 7910575

Offset: 1

Author

Steven Lubars (lubars(AT)gmail.com), Oct 04 2009

Keywords

• base
• nonn

Comments

The digits 2 7 1 8 2 ... are labeled 0, 1, 2, 3, 4, ...

The next term, a(9), is greater than 50 million. - Harvey P. Dale, Apr 01 2017

Examples

			a(6) is the starting position of the second occurrence of the initial 6 decimals of e. the string '271828' occurs at position 252,474, thus a(6) = 252,474.
		

Crossrefs

Cf. A001113, A081876

Programs

Mathematica

Module[{nn=300000,ed},ed=RealDigits[E,10,nn][[1]];Table[ SequencePosition[ ed, Take[ed,n],2][[2]],{n,6}][[All,1]]-1] (* Requires Mathematica version 10 or later *) (* Harvey P. Dale, Apr 01 2017 *)

Extensions

Two more terms -- a(7) and a(8) -- from Harvey P. Dale, Apr 01 2017