OFFSET

1,1

LINKS

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

EXAMPLE

7 is a term since both 7 and 7 + 1 = 8 are negabinary evil numbers (A268272): 7 has 4 digits of 1 in its negabinary representation, 11011, 8 has 2 digits of 1 in its negabinary representation, 11000, and both 4 and 2 are even.

MATHEMATICA

negaBinWt[n_] := negaBinWt[n] = If[n==0, 0, negaBinWt[Quotient[n-1, -2]] + Mod[n, 2]]; evilNegaBinQ[n_] := EvenQ[negaBinWt[n]]; c = 0; k = 1; s = {}; v = Table[-1, {2}]; While[c < 60, If[evilNegaBinQ[k], v = Join[Rest[v], {k}]; If[AllTrue[Differences[v], # == 1 &], c++; AppendTo[s, k - 1]]]; k++]; s

CROSSREFS

KEYWORD

nonn,base

AUTHOR

Amiram Eldar, Jan 28 2020

STATUS

approved