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Numbers whose base-4 representation Sum_{i=0..m} d(i)*4^i has d(m) > d(m-1) < d(m-2) > ...
5

%I #25 Sep 18 2022 19:41:05

%S 0,1,2,3,4,8,9,12,13,14,17,18,19,33,34,35,38,39,49,50,51,54,55,59,68,

%T 72,73,76,77,78,132,136,137,140,141,142,152,153,156,157,158,196,200,

%U 201,204,205,206,216,217,220,221,222,236,237,238

%N Numbers whose base-4 representation Sum_{i=0..m} d(i)*4^i has d(m) > d(m-1) < d(m-2) > ...

%H Harvey P. Dale, <a href="/A032859/b032859.txt">Table of n, a(n) for n = 1..1000</a>

%t Join[{0},Select[Range[250],(Sign/@Differences[IntegerDigits[#,4]]) == PadRight[ {},IntegerLength[#,4]-1,{-1,1}]&]] (* _Harvey P. Dale_, Sep 18 2022 *)

%Y Cf. A007090, A306106.

%Y Cf. A032858..A032865 for bases 3..10.

%Y Cf. A306106..A306111 and A297147 for bases 3..9 and 10.

%K nonn,base

%O 1,3

%A _Clark Kimberling_

%E a(1)=0 inserted by _Georg Fischer_, Dec 18 2020