

A266946


Smallest number of each digital type.


4



1, 10, 11, 100, 101, 102, 110, 111, 1000, 1001, 1002, 1010, 1011, 1012, 1020, 1021, 1022, 1023, 1100, 1101, 1102, 1110, 1111, 10000, 10001, 10002, 10010, 10011, 10012, 10020, 10021, 10022, 10023, 10100, 10101, 10102, 10110, 10111, 10112, 10120, 10121, 10122, 10123, 10200, 10201, 10202, 10203, 10210, 10211, 10212, 10213, 10220, 10221, 10222, 10223, 10230, 10231, 10232, 10233, 10234, 11000, 11001, 11002, 11010, 11011, 11012, 11020, 11021, 11022, 11023, 11100, 11101, 11102, 11110, 11111
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OFFSET

1,2


COMMENTS

The smallest singledigit positive number is 1. This is the first type.
The smallest of the twodigit positive numbers with distinct digits is 10. This is the second type. The smallest of twodigit positive numbers with equal digits is 11. This is the third type, etc.


LINKS



FORMULA

The number of distinct types of kdigit numbers equals A164864(k).


EXAMPLE

The first 3digit number is 100 = a(4).
The following number is 101. It does not belong to the type 100, since the first and the third digits coincide in 101, while in 100 they do not. So 101 is a new type, and a(5)=101.
Next consider 102. Here there are 3 distinct digits, so 102 is a new type, and a(6)=102. However, 103, 104, 105, 106, 107, 108, 109 also have 3 distinct digits, i.e., they belong to type 102.
Further, 110 belongs to neither type 100 nor type 101, since in 110 the first and the second digits coincide, while not in 100 and 101, so a(7)=110; also 111 is a new type, where all digits coincide.
Now we see that every 3digit number is of one of the 5 types a(4), a(5), a(6), a(7), a(8).
Next we consider the first 4digit number a(9)=1000, etc.


CROSSREFS



KEYWORD

nonn,base


AUTHOR



EXTENSIONS



STATUS

approved



