This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A331830 #11 Jan 29 2020 01:42:13
%S A331830 7,13,19,27,31,39,45,51,55,61,67,75,79,87,93,99,107,111,117,123,127,
%T A331830 135,141,147,155,159,167,173,179,183,189,195,203,207,213,219,223,231,
%U A331830 237,243,247,253,259,267,271,279,285,291,299,303,309,315,319,327,333,339
%N A331830 Numbers k such that k and k + 1 are both negabinary evil numbers.
%H A331830 Amiram Eldar, <a href="/A331830/b331830.txt">Table of n, a(n) for n = 1..10000</a>
%e A331830 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.
%t A331830 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
%Y A331830 Cf. A157970, A268272, A331831.
%K A331830 nonn,base
%O A331830 1,1
%A A331830 _Amiram Eldar_, Jan 28 2020