A305074 -id:A305074 - cp's OEIS frontend

8, 40, 72, 104, 136, 168, 200, 232, 264, 296, 328, 360, 392, 424, 456, 488, 520, 552, 584, 616, 648, 680, 712, 744, 776, 808, 840, 872, 904, 936, 968, 1000, 1032, 1064, 1096, 1128, 1160, 1192, 1224, 1256, 1288, 1320, 1352, 1384, 1416, 1448, 1480, 1512, 1544, 1576

Offset: 1

Emeric Deutsch, May 26 2018

a(n) (n>=2) is the second Zagreb index of the single oxide chain SOX(n), defined pictorially in the Simonraj et al. reference (Fig. 4, where SOX(9) is shown marked as OX(1,9)).
The second Zagreb index of a simple connected graph is the sum of the degree products d(i)d(j) over all edges ij of the graph.
The M-polynomial of SL(n) is M(SL(n);x,y) = 2*x^2*y^2 + 2*n*x^2*y^4 + (n  - 2)*x^4*y^4 (n>=2).

Muniru A Asiru, Table of n, a(n) for n = 1..5000
F. Simonraj and A. George, Topological properties of few poly oxide, poly silicate, DOX and DSL networks, International J. of Future Computer and Communication, 2, No. 2, 2013, 90-95.
Index entries for linear recurrences with constant coefficients, signature (2,-1)

Cf. A063164, A305074.

List([1..50], n->32*n-24); # Muniru A Asiru, May 27 2018

Maple
```
seq(32*n - 24, n = 1 .. 50);
```

32*Range[60]-24 (* or *) LinearRecurrence[{2,-1},{8,40},60] (* Harvey P. Dale, Mar 13 2022 *)

Vec(8*x*(1 + 3*x) / (1 - x)^2 + O(x^50)) \\ Colin Barker, May 29 2018

a(n) = A063164(n) for n > 1.
From Colin Barker, May 29 2018: (Start)
G.f.: 8*x*(1 + 3*x) / (1 - x)^2.
a(n) = 2*a(n-1) - a(n-2) for n>2.
(End)

cp's OEIS Frontend

A305075 a(n) = 32*n - 24 (n>=1).

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