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A331891
Negabinary palindromes: nonnegative numbers whose negabinary expansion (A039724) is palindromic.
8
0, 1, 3, 5, 7, 11, 17, 21, 23, 31, 43, 51, 57, 65, 77, 85, 87, 103, 127, 143, 155, 171, 195, 211, 217, 233, 257, 273, 285, 301, 325, 341, 343, 375, 423, 455, 479, 511, 559, 591, 603, 635, 683, 715, 739, 771, 819, 851, 857, 889, 937, 969, 993, 1025, 1073, 1105, 1117
OFFSET
1,3
COMMENTS
Numbers of the form 2^(2*m-1) - 1 (A083420) and 2^(2*m) + 1 (A052539) are terms.
LINKS
EXAMPLE
5 is a term since its negabinary representation is 101 which is palindromic.
MATHEMATICA
negabin[n_] := negabin[n] = If[n==0, 0, negabin[Quotient[n-1, -2]]*10 + Mod[n, 2]]; Select[Range[0, 1200], PalindromeQ @ negabin[#] &]
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Amiram Eldar, Jan 30 2020
STATUS
approved