A182302 Composite numbers that are not perfect powers whose prime factors have equal numbers of bits.

6, 12, 18, 24, 35, 48, 54, 72, 96, 108, 143, 162, 175, 192, 245, 288, 323, 384, 391, 432, 437, 486, 493, 527, 551, 589, 648, 667, 713, 768, 864, 875, 899, 972, 1152, 1458, 1517, 1536, 1573, 1591, 1715, 1739, 1763, 1859, 1927, 1944, 1961, 2021, 2173, 2183, 2257

Offset: 1

Author

Arkadiusz Wesolowski, Apr 23 2012

Keywords

• base
• nonn

Examples

			35 = 5*7 -> 101*111, therefore 35 is a term.
36 = 6^2 -> 10*10*11*11, therefore 36 is not a term.
		

Links

• Arkadiusz Wesolowski, Table of n, a(n) for n = 1..10000

Crossrefs

Subsequence of A200878.

Programs

Mathematica

lst1 = {}; lst2 = {}; r = 2257; Do[b = IntegerDigits[FactorInteger[n], 2]; If[! PrimeQ[n] && Length[b[[-1, 1]]] == Length[b[[1, 1]]], AppendTo[lst1, n]], {n, 4, r}]; lst2 = Complement[lst1, Union[Flatten[Table[n^i, {i, 2, Log[2, r]}, {n, 2, r^(1/i)}]]]]; lst2