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A247546 Numbers k such that d(r,k) = d(s,k), where d(x,k) = k-th binary digit of x, r = {e}, s = {1/e}, and { } = fractional part. 2
4, 6, 7, 11, 12, 15, 16, 17, 18, 19, 20, 22, 23, 26, 30, 32, 33, 34, 38, 39, 41, 43, 45, 46, 47, 53, 55, 57, 61, 62, 63, 64, 65, 66, 67, 68, 69, 71, 74, 76, 82, 83, 89, 90, 91, 92, 93, 94, 96, 97, 98, 99, 100, 103, 104, 106, 108, 109, 110, 111, 112, 113, 114 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Every positive integer lies in exactly one of the sequences A247546 and A247547.

LINKS

Clark Kimberling, Table of n, a(n) for n = 1..1000

EXAMPLE

{e/1} has binary digits 1, 0, 1, 1, 0, 1, 1, 1, 1, 1, 1, 0, 0, 0, 0, 1, 0, 1, ...

{1/e} has binary digits 0, 1, 0, 1, 1, 1, 1, 0, 0, 0, 1, 0, 1, 1, 0, 1, 0, 1, ...

so that a(1) = 4 and a(2) = 6.

MATHEMATICA

z = 200; r = FractionalPart[E]; s = FractionalPart[1/E];

u = Flatten[{ConstantArray[0, -#[[2]]], #[[1]]}] &[RealDigits[r, 2, z]];

v = Flatten[{ConstantArray[0, -#[[2]]], #[[1]]}] &[RealDigits[s, 2, z]];

t = Table[If[u[[n]] == v[[n]], 1, 0], {n, 1, z}];

Flatten[Position[t, 1]]   (* A247546 *)

Flatten[Position[t, 0]]   (* A247547 *)

CROSSREFS

Cf. A247547.

Sequence in context: A103057 A039590 A134038 * A110605 A206775 A287157

Adjacent sequences:  A247543 A247544 A247545 * A247547 A247548 A247549

KEYWORD

nonn,easy,base

AUTHOR

Clark Kimberling, Sep 21 2014

STATUS

approved

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Last modified November 26 17:52 EST 2021. Contains 349343 sequences. (Running on oeis4.)