%I #4 Mar 30 2012 18:35:53
%S 2,4,50,68,70,72,74,352,804,808,810,812,964,966,980,982,986,988,994,
%T 996,998,1002,1004,1006,1016,1018,1020,1022,1026,1028,1030,1048,1060,
%U 1062,1064,1066,1068,1130,1134,1138,1140,1254,1256,1258,1260,1320,1340,2484
%N Numbers n such that the first n decimal digits of e contain equal numbers of even and odd decimal digits.
%C Numbers n such that the first n decimal digits of e contain equal numbers of even and odd decimal digits.
%e 4 is in the sequence because, with 4 digits of e = 2.718 -> (-1)^2 + (-1)^7 + (-1)^1 + (-1)^8 = 0.
%t L= Rest@FoldList[ Plus, 0, (-1)^First@ RealDigits[E, 10, 3000]] ;Do[If [L[[n]]==0,Print[n]],{n,3000}]
%Y Cf. A175793
%K nonn,base
%O 1,1
%A _Michel Lagneau_, Sep 09 2010