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 A192850 Molecular topological indices of the web graphs. 1
 46, 184, 414, 832, 1390, 2232, 3262, 4672, 6318, 8440, 10846, 13824, 17134, 21112, 25470, 30592, 36142, 42552, 49438, 57280, 65646, 75064, 85054, 96192, 107950, 120952, 134622, 149632, 165358, 182520 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Web graphs are defined for n>=3; extended to n=1 using closed form. LINKS G. C. Greubel, Table of n, a(n) for n = 1..1000 Eric Weisstein's World of Mathematics, Molecular Topological Index Index entries for linear recurrences with constant coefficients, signature (2,1,-4,1,2,-1). FORMULA a(n) = n*(6*n^2+22*n+3*((-1)^n+7)). G.f.: 2*x*(x^4+2*x^3+46*x+23)/((x-1)^4*(x+1)^2). - Colin Barker, Aug 07 2012 E.g.f.: x*((49 +40*x +6*x^2)*exp(x) - 3*exp(-x)). - G. C. Greubel, Jan 05 2018 MATHEMATICA Table[n*(6*n^2+22*n+3*((-1)^n+7)), {n, 1, 40}] (* G. C. Greubel, Jan 05 2019 *) PROG (PARI) vector(40, n, n*(6*n^2+22*n+3*((-1)^n+7))) \\ G. C. Greubel, Jan 05 2019 (Magma) [n*(6*n^2+22*n+3*((-1)^n+7)): n in [1..40]]; // G. C. Greubel, Jan 05 2019 (Sage) [n*(6*n^2+22*n+3*((-1)^n+7)) for n in (1..40)] # G. C. Greubel, Jan 05 2019 (GAP) List([1..40], n -> n*(6*n^2+22*n+3*((-1)^n+7))); # G. C. Greubel, Jan 05 2019 CROSSREFS Sequence in context: A251467 A251460 A235767 * A211334 A160334 A235550 Adjacent sequences: A192847 A192848 A192849 * A192851 A192852 A192853 KEYWORD nonn,easy AUTHOR Eric W. Weisstein, Jul 11 2011 STATUS approved

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Last modified September 29 18:32 EDT 2023. Contains 365775 sequences. (Running on oeis4.)