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 A199986 Numbers with digital product = 2. 2
 2, 12, 21, 112, 121, 211, 1112, 1121, 1211, 2111, 11112, 11121, 11211, 12111, 21111, 111112, 111121, 111211, 112111, 121111, 211111, 1111112, 1111121, 1111211, 1112111, 1121111, 1211111, 2111111, 11111112, 11111121, 11111211, 11112111, 11121111, 11211111 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Subsequence of A034049. LINKS Robert Israel, Table of n, a(n) for n = 1..10000 S. Giraudo, Combinatorial operads from monoids, arXiv preprint arXiv:1306.6938, 2013. See Sect. 3.2.1. MAPLE f:= proc(d) local b, i;   b:= (10^d-1)/9;   seq(b+10^i, i=0..d-1); end proc: seq(f(d), d=1..9); # Robert Israel, Jan 13 2021 PROG (PARI) one(n)=if(n, 10^n\9, "") for(n=0, 9, for(m=0, n, print1(one(n-m)2one(m)", "))) \\ Charles R Greathouse IV, Nov 13 2011 CROSSREFS Sequence in context: A053896 A155890 A213969 * A336528 A077410 A211029 Adjacent sequences:  A199983 A199984 A199985 * A199987 A199988 A199989 KEYWORD nonn,easy,base,changed AUTHOR Jaroslav Krizek, Nov 13 2011 STATUS approved

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Last modified January 25 18:03 EST 2021. Contains 340419 sequences. (Running on oeis4.)