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A159940
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The number of trisubstitution products with composition C_n H_(2n-1) X_2 Y.
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1
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4, 16, 46, 106, 208, 364, 586, 886, 1276, 1768, 2374, 3106, 3976, 4996, 6178, 7534, 9076, 10816, 12766, 14938, 17344, 19996, 22906, 26086, 29548, 33304, 37366, 41746, 46456, 51508, 56914, 62686, 68836, 75376, 82318, 89674, 97456, 105676, 114346
(list; graph; refs; listen; history; internal format)
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OFFSET
| 2,1
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COMMENTS
| See the paper by Valentin Vankov Iliev for details.
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REFERENCES
| Valentin Vankov Iliev, "A mathematical characterization of the groups of substitution isomerism of the linear alkanes", J. Math. Chem., 45 (2009), xxx-yyy. Page numbers unknown as of today as it is an 'online first' article.
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FORMULA
| a(n) = (2 n^3 - 9 n^2 + 19 n - 14) where n is the number of carbons.
G.f.: 2*x^2*(2+3*x^2+x^3)/(x-1)^4. [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Apr 28 2009]
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EXAMPLE
| The number of trisubstitution products with composition C_n H_(2n-1) X_2 Y for n = 10 is 1276.
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CROSSREFS
| Cf. A002522, A033816
Sequence in context: A054498 A134139 A097125 * A000704 A007315 A055342
Adjacent sequences: A159937 A159938 A159939 * A159941 A159942 A159943
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KEYWORD
| nonn
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AUTHOR
| Parthasarathy Nambi (PachaNambi(AT)yahoo.com), Apr 26 2009
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EXTENSIONS
| More terms from R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Apr 28 2009
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