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A276795
Folding numbers with an odd number of bits (see A277238 for definition).
2
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
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
KEYWORD
nonn,base
AUTHOR
N. J. A. Sloane, Nov 03 2016
EXTENSIONS
More terms from Lars Blomberg, Nov 09 2016
STATUS
approved