A276795 Folding numbers with an odd number of bits (see A277238 for definition).

1, 6, 22, 28, 78, 90, 108, 120, 286, 310, 346, 370, 412, 436, 472, 496, 1086, 1134, 1206, 1254, 1338, 1386, 1458, 1506, 1596, 1644, 1716, 1764, 1848, 1896, 1968, 2016, 4222, 4318, 4462, 4558, 4726, 4822, 4966, 5062, 5242, 5338, 5482, 5578, 5746, 5842, 5986

Offset

1,2

Comments

Terms greater than 1 are obtained by inserting a 1 in the middle of the binary expansions of the terms of A035928.

Links

Lars Blomberg, Table of n, a(n) for n = 1..10000

Example

78 is binary 1001110. There is a 1 in the center bit. The first 3 bits (100) and the last 3 reversed (011) sums to 111, so 78 is in the sequence.
70 is binary 1000110. There is a 0 in the center bit, thus, despite the fact that the first and last 3 bits have the same relationship as above, 70 is not in the sequence.

Mathematica

{1}~Join~Select[Flatten@ Array[Range[#, 2 # - 1] &[2^#] &[2 (# - 1)] &, 7], If[OddQ@ Length@ # && Take[#, {Ceiling[Length[#]/2]}] == {0}, False, Union[Take[#, Floor[Length[#]/2]] + Reverse@ Take[#, -Floor[ Length[#]/2]]] == {1}] &@ IntegerDigits[#, 2] &] (* Michael De Vlieger, Nov 25 2016 *)

Crossrefs

Cf. A035928, A053738, A277238.

Sequence in context: A044448 A111036 A055709 * A037204 A296981 A035285

Adjacent sequences: A276792 A276793 A276794 * A276796 A276797 A276798

Keyword

nonn,base

Author

N. J. A. Sloane, Nov 03 2016

Extensions

More terms from Lars Blomberg, Nov 09 2016

Status

approved