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A045058 Numbers n with property that in base 4 representation the numbers of 0's and 2's are 4 and 1, respectively. 1
512, 1026, 1032, 1056, 1152, 1536, 2049, 2051, 2052, 2060, 2064, 2096, 2112, 2240, 2304, 2816, 3074, 3080, 3104, 3200, 3584, 4102, 4105, 4107, 4110, 4114, 4120, 4129, 4131, 4132, 4140, 4146, 4152, 4162, 4168, 4192, 4225 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Robert Israel, Table of n, a(n) for n = 1..10000

MAPLE

dmax:= 8: # to get all terms < 4^dmax

T[1, 1, 0]:= {}: T[1, 0, 1]:= {2}: T[1, 0, 0]:= {1, 3}:

for d from 2 to dmax do

  for a from 0 to max(d-1, 4) do

    for b from 0 to max(d-a, 1) do

       T[d, a, b]:= {}:

       if a + b <= d-1 and a < d-1 then

         T[d, a, b]:= T[d, a, b] union map(t -> (4*t+1, 4*t+3), T[d-1, a, b])

       fi;

       if a >= 1 then

         T[d, a, b]:= T[d, a, b] union map(t -> 4*t, T[d-1, a-1, b])

       fi;

       if b >= 1 and a < d-1 then

         T[d, a, b]:= T[d, a, b] union map(t -> 4*t+2, T[d-1, a, b-1])

       fi;

od od od:

sort([seq](op(T[d, 4, 1]), d=5..dmax)); # Robert Israel, Jun 29 2017

MATHEMATICA

Select[Range[4500], DigitCount[#, 4, 0]==4&&DigitCount[#, 4, 2]==1&] (* Harvey P. Dale, May 26 2018 *)

CROSSREFS

Sequence in context: A066648 A043423 A341886 * A220017 A234879 A202454

Adjacent sequences:  A045055 A045056 A045057 * A045059 A045060 A045061

KEYWORD

nonn,base

AUTHOR

Clark Kimberling

STATUS

approved

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Last modified October 6 23:36 EDT 2022. Contains 357270 sequences. (Running on oeis4.)