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A293760
Numbers k such that c(k,0) = c(k,1), where c(k,d) = number of d's in the first k digits of the base-2 expansion of e.
1
2, 4, 32, 34, 36, 44, 46, 52, 54, 56, 58, 60, 62, 64, 66, 68, 96, 104, 108, 114, 226, 228, 230, 252, 254, 270, 296556, 296558, 296560, 296562, 296564, 296574, 296578, 296580, 296584, 296608, 296610, 296612, 296616, 297222, 297226, 297266, 297344, 297346
OFFSET
1,1
COMMENTS
The greatest term in the b-file is a(7129) = 21896286 and there are no further terms up to 100 million binary digits of e. - Harvey P. Dale, Aug 07 2019
LINKS
Harvey P. Dale, Table of n, a(n) for n = 1..7129 (terms < 10^8; first 1489 terms from Robert Price)
EXAMPLE
In base 2, e = 10.10110111111000010..., in which the initial segments of lengths 2 and 4 each have the same number of 0's and 1's.
MATHEMATICA
z = 300; u = N[E, z]; d = RealDigits[u, 2][[1]];
t[n_] := Take[d, n]; c[0, n_] := Count[t[n], 0]; c[1, n_] := Count[t[n], 1];
Table[{n, c[0, n], c[1, n]}, {n, 1, 100}]
Select[Range[z], c[0, #] == c[1, #] &] (* A293760 *)
Position[Accumulate[RealDigits[E, 2, 300000][[1]]/.(0->-1)], 0]//Flatten (* Harvey P. Dale, Aug 07 2019 *)
CROSSREFS
Sequence in context: A019542 A319223 A299783 * A101575 A197099 A009098
KEYWORD
nonn,easy,base
AUTHOR
Clark Kimberling, Oct 18 2017
EXTENSIONS
a(27)-a(44) from Robert Price, Oct 19 2017
STATUS
approved