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A048860
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Smallest denominator d such that the Sylvester expansion of n/d has n terms.
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2
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1, 3, 7, 17, 31, 109, 253, 97, 271, 1621, 199, 3961, 1769, 12013, 16381, 3169, 24991, 15877, 180881, 265201, 2620801, 26753, 781219, 14473441, 693551, 55689349, 18294823
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OFFSET
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1,2
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REFERENCES
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H. T. Freitag and G. M. Phillips, Sylvester's algorithm and Fibonacci numbers, in Applications of Fibonacci numbers, Vol. 8 (Rochester, NY, 1998), 155-163, Kluwer Acad. Publ., Dordrecht, 1999.
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LINKS
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EXAMPLE
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a(3) = 7 since 3/7 = 1/3 + 1/11 + 1/231
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PROG
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(PARI) a(n)=if(n==1, q=1, q=n+1; while(1, c=1; P=n; Q=q; while(Q%P>0, c++; D=Q\P+1; P=P*D-Q; Q*=D); if(c==n, break); q+=n)); return(q)
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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