A175814 Numbers n such that the first n decimal digits of e contain equal numbers of even and odd decimal digits.

2, 4, 50, 68, 70, 72, 74, 352, 804, 808, 810, 812, 964, 966, 980, 982, 986, 988, 994, 996, 998, 1002, 1004, 1006, 1016, 1018, 1020, 1022, 1026, 1028, 1030, 1048, 1060, 1062, 1064, 1066, 1068, 1130, 1134, 1138, 1140, 1254, 1256, 1258, 1260, 1320, 1340, 2484

Offset

1,1

Comments

Numbers n such that the first n decimal digits of e contain equal numbers of even and odd decimal digits.

Links

Table of n, a(n) for n=1..48.

Example

4 is in the sequence because, with 4 digits of e = 2.718 -> (-1)^2 + (-1)^7 + (-1)^1 + (-1)^8 = 0.

Mathematica

L= Rest@FoldList[ Plus, 0, (-1)^First@ RealDigits[E, 10, 3000]] ; Do[If [L[[n]]==0, Print[n]], {n, 3000}]

Crossrefs

Cf. A175793

Sequence in context: A228596 A032019 A181179 * A303382 A303443 A277034

Adjacent sequences: A175811 A175812 A175813 * A175815 A175816 A175817

Keyword

nonn,base

Author

Michel Lagneau, Sep 09 2010

Status

approved