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 A339216 #8 Nov 29 2020 02:10:33 %S A339216 4,13,21,30,37,46,54,78,86,95,102,111,119,128,133,142,150,159,166,175, %T A339216 183,207,215,224,231,240,248,270,278,287,294,303,311,335,343,352,359, %U A339216 368,376,385,390,399,407,416,423,432,440,464,472,481,488,497,505,526,534 %N A339216 Numbers k such that k and k+2 are both binary self numbers (A010061). %C A339216 The least difference between consecutive binary self numbers is 2 (see Macris's proof at A010061). %H A339216 Amiram Eldar, <a href="/A339216/b339216.txt">Table of n, a(n) for n = 1..10000</a> %e A339216 4 is a term since 4 and 6 = 4 + 2 are both binary self numbers. %t A339216 s[n_] := n + DigitCount[n, 2, 1]; m = 550; c = Complement[Range[m], Array[s, m]]; d = Differences[c]; ind = Position[d, 2] // Flatten; c[[ind]] %Y A339216 Cf. A010061. %K A339216 nonn,base %O A339216 1,1 %A A339216 _Amiram Eldar_, Nov 27 2020