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 A201015 Composite numbers whose product of digits is 2. 0
 12, 21, 112, 121, 1112, 1121, 1211, 11112, 11121, 11211, 12111, 21111, 111112, 121111, 211111, 1111112, 1111121, 1112111, 1121111, 1211111, 2111111, 11111112, 11111121, 11111211, 11112111, 11121111, 11211111, 12111111, 21111111, 111111112, 111111121, 111111211 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Complement of A107612 with respect to  A199986. Subsequence of A199981 (composite numbers whose multiplicative digital root is 2). LINKS EXAMPLE Number 121 is in sequence because 1*2*1=2. MATHEMATICA Sort[Select[FromDigits/@Flatten[Table[Permutations[Join[{2}, PadRight[ {}, n, 1]]], {n, 10}], 1], CompositeQ]] (* Harvey P. Dale, Oct 23 2015 *) CROSSREFS Cf. A107612 (primes whose product of digits is 2), A199986 (numbers whose product of digits is 2). Sequence in context: A039402 A043225 A111066 * A044005 A321771 A225864 Adjacent sequences:  A201012 A201013 A201014 * A201016 A201017 A201018 KEYWORD nonn,base AUTHOR Jaroslav Krizek, Nov 25 2011 STATUS approved

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Last modified February 26 08:33 EST 2020. Contains 332277 sequences. (Running on oeis4.)