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 A337079 #9 Sep 02 2023 19:01:11
%S A337079 1,1,1,1,2,2,5,8,18,35,61,98,187,304,492,880,1583,2779,5196,9407,
%T A337079 17387,31772,58450,106360,193875,351836,642844,1173333,2155913,
%U A337079 3993379,7466547,14048253,26680668,50751057,97052665,185557893,354235368,674995568,1284856970
%N A337079 The number of twin binary Niven numbers (k, k+1) such that k <= 2^n.
%H A337079 Jean-Marie De Koninck, Nicolas Doyon and Imre Kátai, <a href="https://doi.org/10.1007/s11139-008-9127-z">Counting the number of twin Niven numbers</a>, The Ramanujan Journal, Vol. 17, No .1 (2008), pp. 89-105, <a href="https://www.researchgate.net/publication/225198389_Counting_the_number_of_twin_Niven_numbers">alternative link</a>.
%F A337079 a(n) ~ c * 2^n/n^2, where c is a constant (consequence of the theorem of De Koninck et al., 2008). Apparently c ~ 0.28.
%e A337079 a(5) = 2 since there are two binary Niven numbers k below 2^5 = 32 such that k+1 is also a binary Niven number: 1 and 20.
%t A337079 binNivenQ[n_] := Divisible[n, DigitCount[n, 2, 1]]; s = {}; c = 0; p = 2; q1 = True; Do[q2 = binNivenQ[n]; If[q1 && q2, c++]; If[n - 1 == p, AppendTo[s, c]; p *= 2]; q1 = q2, {n, 2, 2^20}]; s
%Y A337079 Cf. A049445, A330931, A337078.
%K A337079 nonn,base
%O A337079 1,5
%A A337079 _Amiram Eldar_, Aug 14 2020