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%I #9 Sep 30 2024 12:39:41
%S 0,1,10,11,100,101,1000,1001,1010,10000,10001,10010,100000,100001,
%T 100010,100011,1000000,1000001,1000010,1000011,10000000,10000001,
%U 10000010,10000011,10000100,100000000,100000001,100000010,100000011,100000100,1000000000,1000000001
%N n in base whose greedy place values are quarter-squares (A002620).
%e The quarter-square base is A002620 = (1,2,4,6,9,12,16,...), in which 15 = 12 + 2 + 1, written in quarter-square base as 100011.
%t greedy[list_, n_] := Reap[FoldList[(Sow[Quotient[#1, #2]]; Mod[#1, #2]) &, n, Reverse[list]]][[2, 1]];
%t seq = Table[Floor[((n + 1)^2)/4], {n, 20}]; (*A002620*)
%t Table[FromDigits[greedy[seq, n]], {n, Last[seq]}]
%t (* _Peter J. C. Moses_, Oct 18 2012; from A214973 *)
%Y Cf. A002620, A376451, A376452, A376453.
%K nonn,base
%O 0,3
%A _Clark Kimberling_, Sep 25 2024