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 A102393 #13 Aug 02 2020 04:12:27 %S A102393 1,0,0,4,0,6,7,0,0,10,11,0,13,0,0,16,0,18,19,0,21,0,0,24,25,0,0,28,0, %T A102393 30,31,0,0,34,35,0,37,0,0,40,41,0,0,44,0,46,47,0,49,0,0,52,0,54,55,0, %U A102393 0,58,59,0,61,0,0,64,0,66,67,0,69,0,0,72,73,0,0,76,0,78,79,0,81,0,0,84,0,86 %N A102393 A wicked evil sequence. %C A102393 Elements of A026147 (evil numbers plus one) appear at positions indexed by the evil numbers A001969, 0 otherwise. A000027(n) = A102393(n) + A102394(n). %C A102393 The following sequences all appear to have the same parity: A003071, A029886, A061297, A092524, A093431, A102393, A104258, A122248, A128975. - _Jeremy Gardiner_, Dec 28 2008 %H A102393 Tanya Khovanova, <a href="http://arxiv.org/abs/1410.2193">There are no coincidences</a>, arXiv preprint 1410.2193 [math.CO], 2014. %F A102393 a(n) = (n+1)(1+(-1)^A000120(n))/2. %F A102393 a(n) = (n+1)(1+(-1)^A010060(n))/2. %t A102393 a[n_] := If[EvenQ @ DigitCount[n, 2, 1], n + 1, 0]; Array[a, 100, 0] (* _Amiram Eldar_, Aug 02 2020 *) %Y A102393 Cf. A000027, A000120, A001969, A010060, A026147, A102391, A102393, A102394. %Y A102393 Cf. A003071, A029886, A061297, A092524, A093431, A104258, A122248, A128975. %K A102393 easy,nonn %O A102393 0,4 %A A102393 _Paul Barry_, Jan 06 2005