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A073727
Number of distinct-digit integers between squares.
0
2, 4, 5, 7, 9, 11, 13, 14, 16, 9, 18, 20, 21, 18, 20, 26, 26, 22, 30, 32, 28, 35, 29, 38, 33, 41, 36, 44, 38, 49, 23, 46, 7, 7, 46, 36, 42, 43, 48, 43, 51, 44, 46, 44, 56, 49, 1, 54, 55, 56, 57, 59, 60, 53, 60, 62, 35, 43, 68, 71, 64, 74, 67, 72, 66, 31, 73, 75, 75, 77, 79, 86
OFFSET
1,1
COMMENTS
The number of distinct-digit integers is finite therefore the sequence contains only zeros after n=31427. The last nonzero terms are a(31420)=492, a(31421)=414, a(31422)=378, a(31423)=648, a(31424)=382, a(31425)=338, a(31426)=720 and a(31427)=0, a(31428)=0...
EXAMPLE
a(10)=9 because between 10^2 and 11^2 there are 9 integers with distinct digits: 102, 103, 104, 105, 106, 107, 108, 109, 120.
MATHEMATICA
Table[Length[Select[Table[n, {n, x^2+1, (x+1)^2-1}], Length[IntegerDigits[ # ]]==Length[Union[IntegerDigits[ # ]]]&]], {x, 31428}]
CROSSREFS
Sequence in context: A301728 A005152 A060831 * A075692 A112235 A287175
KEYWORD
nonn,base
AUTHOR
Zak Seidov, Sep 01 2002
STATUS
approved