A258410 Nonnegative integers with an equal number of occurrences of all digits in bijective base-2 numeration.

4, 5, 18, 20, 21, 24, 25, 27, 70, 74, 76, 77, 82, 84, 85, 88, 89, 91, 98, 100, 101, 104, 105, 107, 112, 113, 115, 119, 270, 278, 282, 284, 285, 294, 298, 300, 301, 306, 308, 309, 312, 313, 315, 326, 330, 332, 333, 338, 340, 341, 344, 345, 347, 354, 356, 357

Offset: 1

Author

Alois P. Heinz, May 29 2015

Keywords

• nonn
• base

Examples

			4 = 12_bij2, 5 = 21_bij2, 18 = 1122_bij2, 20 = 1212_bij2.
		

Links

• Alois P. Heinz, Table of n, a(n) for n = 1..10000
• Wikipedia, Bijective numeration

Crossrefs

Cf. A007931, A214676, A257869, A258411.

Programs

Maple

p:= proc(n) local d, m, r; m:= n; r:= 0;
      while m>0 do d:= irem(m, 2, 'm');
        if d=0 then d:=2; m:= m-1 fi;
        r:= r+x^d
      od;
      simplify(r/(x+x^2))::integer
    end:
a:= proc(n) option remember; local k;
      for k from 1+`if`(n=1, 0, a(n-1)) by 1
      while not p(k) do od; k
    end:
seq(a(n), n=1..70);