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A214731
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a(n) = n^3 - 2*n^2 - 1.
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2
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-2, -1, 8, 31, 74, 143, 244, 383, 566, 799, 1088, 1439, 1858, 2351, 2924, 3583, 4334, 5183, 6136, 7199, 8378, 9679, 11108, 12671, 14374, 16223, 18224, 20383, 22706, 25199, 27868, 30719, 33758, 36991, 40424, 44063, 47914, 51983, 56276, 60799, 65558, 70559
(list;
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refs;
listen;
history;
text;
internal format)
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OFFSET
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1,1
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LINKS
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FORMULA
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G.f.: -x*(2-7*x-x^3)/(1-x)^4.
a(n) - a(n-2) = A080859(n-2) - 1 for n>2. (End)
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MAPLE
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MATHEMATICA
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PROG
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(SageMath) [n^2*(n-2)-1 for n in range(1, 51)] # G. C. Greubel, Dec 31 2023
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CROSSREFS
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Similar sequences: A152015 (of the type m^3+2m^2-1), A081437 (m^3-2m^2+1).
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KEYWORD
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sign,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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