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A280428
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a(n) = 1729*n^3.
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1
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1729, 13832, 46683, 110656, 216125, 373464, 593047, 885248, 1260441, 1729000, 2301299, 2987712, 3798613, 4744376, 5835375, 7081984, 8494577, 10083528, 11859211, 13832000, 16012269, 18410392, 21036743, 23901696, 27015625, 30388904, 34031907, 37955008, 42168581, 46683000
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OFFSET
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1,1
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COMMENTS
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Previous name was: Taxi-cab numbers of form n^3*1729; in other words, taxi-cab numbers of form n^3*A001235(1).
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LINKS
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FORMULA
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a(n) = n^3 * 1729.
a(n) = 4*a(n-1) - 6*a(n-2) + 4*a(n-3) - a(n-4) for n > 4.
G.f.: x*(1729*x^2 + 6916*x + 1729)/(x - 1)^4. (End)
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EXAMPLE
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For n = 11, a(11) = 11^3 * 1729 = 2301299 and a(11) = A001235(67).
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MATHEMATICA
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PROG
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(PARI) vector(n, 30, 1729*n^3) \\ Derek Orr, Mar 05 2017
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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