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A293541
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a(1)=1; for n>1, a(n) = least integer greater than a(n-1) such that the numbers of divisors of the pairwise sums of a(1),...,a(n) are all distinct.
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1
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OFFSET
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1,2
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LINKS
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EXAMPLE
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Let d(n) be the number of divisors of n. Then a(2)!=2 because d(1+1)=d(1+2)=2. a(2)=3 because d(1+1)=2, d(1+3)=3, and d(3+3)=4 are all distinct.
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CROSSREFS
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KEYWORD
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more,nonn
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AUTHOR
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STATUS
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approved
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