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Search: id:A102049
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| A102049 |
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Indices of primes which are denominators of convergents to e. |
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+0
3
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OFFSET
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1,1
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COMMENT
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The prime denominators of convergents to e form A094008 (so A000040(a(n)) = A094008(n)). Their positions in A007677 (denominators of convergents to e) form A094007, so a(n) = A000720(A007677(A094007(n))).
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REFERENCES
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E. B. Burger, Diophantine Olympics ..., Amer. Math. Monthly, 107 (Nov. 2000), 822-829.
J. Sondow, A geometric proof that e is irrational and a new measure of its irrationality, Amer. Math. Monthly, to appear.
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LINKS
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Eric Weisstein's World of Mathematics, Link to a section of The World of Mathematics\.
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FORMULA
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a(n) = A000720(A094008(n)).
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EXAMPLE
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a(1) = 2 because the first convergent to e with prime denominator is 8/3 and the index of 3 is 2, i.e., 3 is the 2nd prime.
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CROSSREFS
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Cf. A000040, A000720, A007677, A094007, A094008.
Sequence in context: A132498 A087314 A099179 this_sequence A058522 A122736 A092458
Adjacent sequences: A102046 A102047 A102048 this_sequence A102050 A102051 A102052
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KEYWORD
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nonn
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AUTHOR
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Jonathan Sondow (jsondow(AT)alumni.princeton.edu), Dec 27 2004
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