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A069257
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Denominator of the last term of the Egyptian fraction sum (using the greedy algorithm) which satisfies 1 = 1/n + 1/(n+1) + 1/(n+2) ... 1/a(n).
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2
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6, 20, 57960, 3145940416080, 5765760, 288680192354725622464710969631440008928, 20484953806009937929429725901717124022833778640, 59553628273094395440, 102119994931499628863688098762720537989600
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OFFSET
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2,1
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COMMENTS
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The next term in the series, a(11), is 7*10^192.
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LINKS
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EXAMPLE
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Since 1 = 1/3 + 1/4 + 1/5 + 1/6 + 1/20, a(3) = 20.
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MATHEMATICA
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a[n_] := Module[{s = 1/n, k = n}, While[s < 1, k = Max[k + 1, Ceiling[1/(1 - s)]]; s += 1/k]; k]; Array[a, 9, 2] (* Amiram Eldar, Oct 18 2019 *)
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CROSSREFS
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KEYWORD
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easy,frac,nonn
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AUTHOR
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Christopher Lund (clund(AT)san.rr.com), Apr 14 2002
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STATUS
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approved
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