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A028889
Numbers whose iterated product of digits is a power of 2.
3
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
1,2
LINKS
EXAMPLE
38 -> 3*8 = 24 -> 2*4 = 8 = 2^3.
MATHEMATICA
p2Q[n_]:=IntegerQ[Log[2, NestWhile[Times@@IntegerDigits[#]&, n, #>9&]]]; Select[ Range[200], p2Q] (* Harvey P. Dale, Sep 19 2019 *)
CROSSREFS
KEYWORD
nonn,base
EXTENSIONS
Extended (and corrected) by Scott Lindhurst (ScottL(AT)alumni.princeton.edu)
STATUS
approved