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

Author

N. J. A. Sloane, Nov 03 2016

Keywords

• nonn
• base

Comments

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

Examples

			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.
		

Links

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

Crossrefs

Cf. A035928, A053738, A277238.

Programs

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 *)

Extensions

More terms from Lars Blomberg, Nov 09 2016