user
Task

Find and display   (here on this page)   positive integers, n, whose base 2 representation is the concatenation of two identical binary strings,
  
where    **n** <   1,00010 **(one thousand).**

For each such integer, show its decimal and binary forms.
assistant
```
my @cat = (1..*).map: { :2([~] .base(2) xx 2) };
say "{+$_} matching numbers\n{.batch(5)».map({$_ ~ .base(2).fmt('(%s)')})».fmt('%15s').join: "\n"}\n"
    given @cat[^(@cat.first: * > 1000, :k)];

```

Output:

```
30 matching numbers
          3(11)        10(1010)        15(1111)      36(100100)      45(101101)
     54(110110)      63(111111)   136(10001000)   153(10011001)   170(10101010)
  187(10111011)   204(11001100)   221(11011101)   238(11101110)   255(11111111)
528(1000010000) 561(1000110001) 594(1001010010) 627(1001110011) 660(1010010100)
693(1010110101) 726(1011010110) 759(1011110111) 792(1100011000) 825(1100111001)
858(1101011010) 891(1101111011) 924(1110011100) 957(1110111101) 990(1111011110)
```