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A111066 Numbers with digits 1 and 2 and at least one of each. 3
12, 21, 112, 121, 122, 211, 212, 221, 1112, 1121, 1122, 1211, 1212, 1221, 1222, 2111, 2112, 2121, 2122, 2211, 2212, 2221, 11112, 11121, 11122, 11211, 11212, 11221, 11222, 12111, 12112, 12121, 12122, 12211, 12212, 12221, 12222, 21111, 21112 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

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

MATHEMATICA

FromDigits /@ Select[ IntegerDigits[ Range[210], 3], Union[ # ] == {1, 2} &] (* Robert G. Wilson v *)

Union[FromDigits/@Select[Flatten[Table[Tuples[{1, 2}, n], {n, 2, 5}], 1], Union[#] == {1, 2}&]] (* Harvey P. Dale, Sep 05 2013 *)

CROSSREFS

Equals A007931 minus A000042 and A002276; cf. A043494, A037415, A062289, A000225.

Sequence in context: A048344 A039402 A043225 * A201015 A044005 A321771

Adjacent sequences:  A111063 A111064 A111065 * A111067 A111068 A111069

KEYWORD

easy,nonn,base

AUTHOR

Alexandre Wajnberg & Youri Mora, Oct 08 2005

EXTENSIONS

More terms from Robert G. Wilson v, Oct 09 2005

Crossrefs from Charles R Greathouse IV, Aug 03 2010

STATUS

approved

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Last modified March 31 16:44 EDT 2020. Contains 333151 sequences. (Running on oeis4.)