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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

%I #28 Nov 06 2023 02:59:48

%S 2,4,32,34,36,44,46,52,54,56,58,60,62,64,66,68,96,104,108,114,226,228,

%T 230,252,254,270,296556,296558,296560,296562,296564,296574,296578,

%U 296580,296584,296608,296610,296612,296616,297222,297226,297266,297344,297346

%N 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.

%C 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

%H Harvey P. Dale, <a href="/A293760/b293760.txt">Table of n, a(n) for n = 1..7129</a> (terms < 10^8; first 1489 terms from Robert Price)

%e 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.

%t z = 300; u = N[E, z]; d = RealDigits[u, 2][[1]];

%t t[n_] := Take[d, n]; c[0, n_] := Count[t[n], 0]; c[1, n_] := Count[t[n], 1];

%t Table[{n, c[0, n], c[1, n]}, {n, 1, 100}]

%t Select[Range[z], c[0, #] == c[1, #] &] (* A293760 *)

%t Position[Accumulate[RealDigits[E,2,300000][[1]]/.(0->-1)],0]//Flatten (* _Harvey P. Dale_, Aug 07 2019 *)

%Y Cf. A004593, A029624.

%K nonn,easy,base

%O 1,1

%A _Clark Kimberling_, Oct 18 2017

%E a(27)-a(44) from _Robert Price_, Oct 19 2017

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Last modified August 24 11:44 EDT 2024. Contains 375410 sequences. (Running on oeis4.)