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%I #21 May 21 2023 12:23:28
%S 3,7,12,13,19,23,28,29,48,49,52,53,67,71,76,77,83,87,92,93,112,113,
%T 116,117,192,193,196,197,208,209,212,213,259,263,268,269,275,279,284,
%U 285,304,305,308,309,323,327,332,333,339,343,348
%N Numbers whose base-4 representation contains no 2's and exactly one 3.
%H Robert Israel, <a href="/A045134/b045134.txt">Table of n, a(n) for n = 1..10000</a>
%F From _Robert Israel_, Sep 20 2016: (Start)
%F a(m+(n+1)*2^n) = a(m) + 4^(n+1) for 1 <= m <= (n+1)*2^n.
%F a(m+(n+1)*2^n) = A000695(m-(n+1)*2^n-1) + 3*4^(n+1) for (n+1)*2^n < m <= (n+2)*2^n. (End)
%p N:= 5: # to get all terms < 4^(N+1)
%p B0:= {0,1}:
%p B1:= {3}:
%p for d from 1 to N do
%p B1:= B1 union map(`+`,B0, 3*4^d) union map(`+`,B1,4^d);
%p B0:= B0 union map(`+`, B0,4^d);
%p od:
%p sort(convert(B1,list)); # _Robert Israel_, Sep 20 2016
%t Select[Range[400],DigitCount[#,4,2]==0&&DigitCount[#,4,3]==1&] (* _Harvey P. Dale_, Dec 25 2012 *)
%Y Cf. A000695, A007090.
%K nonn,base
%O 1,1
%A _Clark Kimberling_
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