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A278465 Numbers that are the sum of one or two terms of A035928.

%I A278465 #18 May 09 2021 02:16:21
%S A278465 2,4,10,12,14,20,22,24,38,40,42,44,48,50,52,54,56,58,62,64,66,68,76,
%T A278465 80,84,90,94,98,104,108,112,142,144,150,152,154,160,162,170,172,178,
%U A278465 180,182,184,188,190,192,194,198,202,204,206,208,212,214,216,220,222,224,226,230,232,234,240,242,244,246,250,252,254,256,260
%N A278465 Numbers that are the sum of one or two terms of A035928.
%H A278465 Robert Israel, <a href="/A278465/b278465.txt">Table of n, a(n) for n = 1..10000</a>
%p A278465 N:= 1000: # to get all terms <= N
%p A278465 bcr:= proc(n) local L,m;
%p A278465   L:= convert(n,base,2);
%p A278465   m:= nops(L);
%p A278465   add((1-L[i])*2^(m-i),i=1..m)
%p A278465 end proc:
%p A278465 A035928:= select(`<=`,{seq(seq(x*2^d + bcr(x), x=2^(d-1)..2^d-1),d=1..(ilog2(N)+1)/2)},N):
%p A278465 sort(convert(A035928 union {seq(seq(A035928[i]+t, t = select(`<=`,A035928[i..-1], N-A035928[i])),i=1..nops(A035928))},list)); # _Robert Israel_, Nov 23 2016
%t A278465 max = 1000;
%t A278465 bcrQ[n_] := Module[{idn2 = IntegerDigits[n, 2]}, Reverse[idn2 /. {1 -> 0, 0 -> 1}] == idn2];
%t A278465 A035928 = Select[Range[max], bcrQ];
%t A278465 Union[Total /@ Tuples[A035928, 2], A035928] // Select[#, # <= max&]& (* _Jean-François Alcover_, Jul 29 2020, after _Harvey P. Dale_ in A035928 *)
%Y A278465 Cf. A035928.
%K A278465 nonn
%O A278465 1,1
%A A278465 _Jeffrey Shallit_, Nov 22 2016