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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 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

Numbers of the form 2^(2*m-1) - 1 (A083420) and 2^(2*m) + 1 (A052539) are terms.

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..10000

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

Cf. A002113, A006995, A014190, A039724, A094202, A331191.

Sequence in context: A211409 A152998 A222176 * A331896 A108539 A170886

Adjacent sequences:  A331888 A331889 A331890 * A331892 A331893 A331894

KEYWORD

nonn,base

AUTHOR

Amiram Eldar, Jan 30 2020

STATUS

approved

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Last modified June 13 22:55 EDT 2021. Contains 345016 sequences. (Running on oeis4.)