A032882 - OEIS

%I #13 Feb 12 2021 21:39:42

%S 1,2,3,6,7,15,16,30,33,34,57,60,61,69,70,138,141,142,150,151,273,276,

%T 277,300,303,304,312,313,516,519,520,543,546,547,555,556,624,627,628,

%U 636,637,1245,1248,1249,1272,1275,1276,1284,1285,1353,1356,1357,1365

%N Numbers whose base-3 representation Sum_{i=0..m} d(i)*3^i has d(0) < d(1) > d(2) < ...

%H Robert Israel, <a href="/A032882/b032882.txt">Table of n, a(n) for n = 1..10000</a>

%p f:= proc(L,d) option remember; local i;

%p   if d::even then seq([op(L),i],i=L[-1]+1..2)

%p   else seq([op(L),i],i=0..L[-1]-1)

%p   fi

%p end proc:

%p S[1]:= {[0],[1],[2]}:

%p for d from 2 to 10 do S[d]:= map(f,S[d-1],d) od:

%p A:= {}:

%p for d from 1 to 10 do

%p   A:= A union map(proc(L) local i; add(L[i]*3^(i-1),i=1..nops(L)) end proc, select(L -> L[-1]>0, S[d]))

%p od:

%p sort(convert(A,list)); # _Robert Israel_, Jan 05 2021

%K nonn,base

%O 1,2

%A _Clark Kimberling_