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%I #27 Sep 08 2022 08:46:17
%S -14,60,134,208,282,356,430,504,578,652,726,800,874,948,1022,1096,
%T 1170,1244,1318,1392,1466,1540,1614,1688,1762,1836,1910,1984,2058,
%U 2132,2206,2280,2354,2428,2502,2576,2650,2724,2798,2872,2946,3020,3094,3168
%N a(n) = 74*n - 14.
%C For n >= 1, a(n) is the first Zagreb index of the tetrameric 1,3-adamantane TA[n]. The first Zagreb index of a simple connected graph is the sum of the squared degrees of its vertices. Alternately, it is the sum of the degree sums d(i) + d(j) over all edges ij of the graph. The pictorial definition of the tetrameric 1,3-adamantane can be viewed in the G. H. Fath-Tabar et al. reference.
%C The M-polynomial of the tetrameric 1,3-adamantane TA[n] is M(TA[n], x, y) = 6*(n+1)*x^2*y^3 + 6*(n-1)*x^2*y^4 + (n-1)*x^4*y^4.
%H Emeric Deutsch and Sandi Klavžar, <a href="http://dx.doi.org/10.22052/ijmc.2015.10106">M-polynomial and degree-based topological indices</a>, Iranian J. Math. Chemistry, 6, No. 2, 2015, 93-102.
%H G. H. Fath-Tabar, A. Azad, and N. Elahinezhad, <a href="http://en.journals.sid.ir/ViewPaper.aspx?ID=254060">Some topological indices of tetrameric 1,3-adamantane</a>, Iranian J. Math. Chemistry, 1, No. 1, 2010, 111-118.
%H Ivan Gutman and Kinkar C. Das, <a href="http://match.pmf.kg.ac.rs/electronic_versions/Match50/match50_83-92.pdf">The first Zagreb index 30 years after</a>, MATCH Commun. Math. Comput. Chem. 50, 2004, 83-92.
%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (2,-1).
%F G.f.: 2*(44*x - 7)/(1-x)^2.
%F a(n) = 2*a(n-1) - a(n-2). - _Vincenzo Librandi_, Nov 13 2016
%p seq(74*n-14, n = 0..40);
%t Table[74n - 14, {n, 0, 50}] (* _Harvey P. Dale_, Mar 08 2020 *)
%o (Magma) [74*n-14: n in [0..45]]; // _Vincenzo Librandi_, Nov 13 2016
%o (Scala) (0 to 48).map(74 * _ - 14) // _Alonso del Arte_, Mar 11 2020
%Y Cf. A277987.
%K sign,easy
%O 0,1
%A _Emeric Deutsch_, Nov 12 2016
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