A028889 Numbers whose iterated product of digits is a power of 2.

1, 2, 4, 8, 11, 12, 14, 18, 21, 22, 24, 26, 27, 29, 34, 36, 37, 38, 39, 41, 42, 43, 46, 49, 62, 63, 64, 66, 67, 72, 73, 76, 77, 79, 81, 83, 88, 89, 92, 93, 94, 97, 98, 99, 111, 112, 114, 118, 121, 122, 124, 126, 127, 129, 134, 136, 137, 138, 139, 141, 142, 143, 146, 149, 162, 163, 164, 166, 167

Offset: 1

Author

N. J. A. Sloane

Keywords

• nonn
• base

Examples

			38 -> 3*8 = 24 -> 2*4 = 8 = 2^3.
		

Links

• Harvey P. Dale, Table of n, a(n) for n = 1..1000

Crossrefs

Cf. A031347, A028846, A028836.

Programs

Mathematica

p2Q[n_]:=IntegerQ[Log[2,NestWhile[Times@@IntegerDigits[#]&,n,#>9&]]]; Select[ Range[200],p2Q] (* Harvey P. Dale, Sep 19 2019 *)

Extensions

Extended (and corrected) by Scott Lindhurst (ScottL(AT)alumni.princeton.edu)