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A121318
Molecular topological indices of the path graphs P_n
0
0, 4, 16, 38, 74, 128, 204, 306, 438, 604, 808, 1054, 1346, 1688, 2084, 2538, 3054, 3636, 4288, 5014, 5818, 6704, 7676, 8738, 9894, 11148, 12504, 13966, 15538, 17224, 19028, 20954, 23006, 25188, 27504, 29958, 32554, 35296, 38188, 41234, 44438
OFFSET
1,2
COMMENTS
Maximum molecular topological index for alkane trees with n vertices.
See page 161 of Muller et al. paper for the definition of molecular topological index.
REFERENCES
W. R. Muller, K. Szymanski, J.V. Knop and N. Trinajstich, "Molecular topological index", J. Chem. Inf. Comput. Sci., vol. 30 (1990),pp. 160-163. See Table 2 on page 162 column 4.
LINKS
Eric Weisstein's World of Mathematics, Molecular Topological Index
Eric Weisstein's World of Mathematics, Path Graph
FORMULA
a(1) = 0; a(n) = (2n^3-3n^2+13n-18)/3 - Eric W. Weisstein, Jul 10 2011.
G.f.: 2*x^2*(x+1)*(2-2*x+x^2)/(1-x)^4. - Colin Barker, Aug 07 2012
EXAMPLE
If n=10 then the maximum molecular topological index is 604 which is the tenth term in the sequence.
CROSSREFS
Cf. A000602.
Sequence in context: A203299 A198015 A103770 * A152133 A371345 A297361
KEYWORD
nonn,easy
AUTHOR
Parthasarathy Nambi, Aug 25 2006
STATUS
approved