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Search: id:A090884
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| A090884 |
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There exists an isomorphism from the positive rationals under multiplication to Z[x] under addition, defined by f(q) = e1 + (e2)x + (e3)(x^2) +...+ (ek)(x^(k-1)) + ... (where e_i is the exponent of the i-th prime in q's prime factorization) The a(n) above are calculated by a(n) = f^(-1)[d/dx f(n)] (In other words: differentiate n's image in Z[x] and return to Q). |
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6
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| 1, 1, 2, 1, 9, 2, 125, 1, 4, 9, 2401, 2, 161051, 125, 18, 1, 4826809, 4, 410338673, 9, 250, 2401, 16983563041, 2, 81, 161051, 8, 125, 1801152661463, 18, 420707233300201, 1, 4802, 4826809, 1125, 4, 25408476896404831, 410338673, 322102, 9
(list; graph; listen)
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OFFSET
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1,3
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REFERENCES
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Joseph J. Rotman, The Theory of Groups: An Introduction, 2nd ed. Boston: Allyn and Bacon, Inc. 1973. Page 9, problem 1.26.
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LINKS
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Sam Alexander, Post to sci.math.
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CROSSREFS
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Cf. A001222, A048675, A054841, A090880, A090881, A090882, A090883.
Sequence in context: A030327 A095890 A021460 this_sequence A095888 A124776 A099285
Adjacent sequences: A090881 A090882 A090883 this_sequence A090885 A090886 A090887
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KEYWORD
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easy,nonn
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AUTHOR
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Sam Alexander (amnalexander(AT)yahoo.com), Dec 12 2003
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EXTENSIONS
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More terms from Ray Chandler (rayjchandler(AT)sbcglobal.net), Dec 20 2003
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