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%I #12 May 23 2023 05:41:45
%S 12303,12339,12348,12483,12492,12528,13059,13068,13104,13248,15363,
%T 15372,15408,15552,16128,16447,16591,16627,16636,17167,17203,17212,
%U 17347,17356,17392,19471,19507,19516,19651,19660
%N Numbers whose base-4 representation contains exactly four 0's and three 3's.
%H Robert Israel, <a href="/A045084/b045084.txt">Table of n, a(n) for n = 1..10000</a>
%p Res:= NULL:
%p for d from 7 to 8 do
%p for i from 0 to d-7 do
%p L:= [0$4, 3$3, 1$i,2$(d-7-i)];
%p P:= remove(t -> t[-1]=0, combinat:-permute(L));
%p Res:= Res,op(map(t -> add(t[i]*4^(i-1),i=1..d), P));
%p od od:
%p sort([Res]); # _Robert Israel_, Feb 27 2018
%Y Cf. A007090.
%K nonn,base
%O 1,1
%A _Clark Kimberling_
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