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A181960
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Number of distinct nonnegative integers that can be generated by an expression containing n binary operators (any of add, subtract, multiply and divide) whose operands are any integer between 1 and 9; parenthesis allowed.
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5
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OFFSET
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0,1
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LINKS
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EXAMPLE
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a(1)=40, the distinct values are: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 20 21 24 25 27 28 30 32 35 36 40 42 45 48 49 54 56 63 64 72 81
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CROSSREFS
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KEYWORD
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nonn,more
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AUTHOR
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STATUS
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approved
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