A212440 Numbers with even curling numbers of their binary representations, cf. A181935.

3, 4, 10, 11, 12, 15, 16, 19, 20, 21, 26, 27, 28, 35, 36, 37, 43, 44, 45, 47, 48, 51, 52, 53, 54, 58, 59, 60, 63, 64, 67, 68, 69, 73, 74, 75, 76, 79, 80, 82, 83, 84, 90, 91, 92, 99, 100, 101, 107, 108, 109, 111, 112, 115, 116, 117, 118, 122, 123, 124, 131

Offset

1,1

Links

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

Index entries for sequences related to binary expansion of n.

Formula

A212412(a(n)) = 0.

Mathematica

f[n_, e_] := Module[{d = IntegerDigits[n, 2^e]}, Length[Split[d][[-1]]] - If[SameQ @@ d && Mod[n, 2^e] < 2^(e - 1), 1, 0]]; q[n_] := EvenQ[Max[Table[f[n, e], {e, Range[Max[1, Floor[Log2[n]]]]}]]]; q[0] = False; Select[Range[0, 150], q] (* Amiram Eldar, Apr 08 2025 *)

Prog

(Haskell)
a212440 n = a212440_list !! (n-1)
a212440_list = filter (even . a181935) [0..]

Crossrefs

Complement of A212441.

Cf. A181935, A212412.

Sequence in context: A117781 A075100 A288660 * A066861 A292564 A191192

Adjacent sequences: A212437 A212438 A212439 * A212441 A212442 A212443

Keyword

nonn,base

Author

Reinhard Zumkeller, May 17 2012

Status

approved