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. 2024 Jun 7;14:13150. doi: 10.1038/s41598-024-63007-w

Table 1.

Description and derivation of various TI’s obtained from the M-polynomial and NM-polynomial where Dx=x((z(x,y))x), Dy=y((z(x,y))y), Sx=0xz(t,y)tdt, Sy=0yz(x,t)tdt, J(z(x,y))=z(x,x), Qα(z(x,y))=xαz(x,y) For D based TI’s: Δ(u)=du, Δ(v)=dv, z(x,y)=M(G;x,y) for NBD based TI’s: Δ(u)=ndu, Δ(v)=ndv, z(x,y)=NM(G;x,y).

Topological index (TI) Formula g(Δ(u),Δ(v)) Derivation from z(x,y) = M(G;x,y) or NM(G;x,y) References of TI’s first introduced:
1st Zagreb index: M1(G) uvE(G)i(Δ(u)+Δ(v)) (Dx+Dy)(z(x,y))x=y=1 44
3rd version Zagreb index: NM1(G)
2nd Zagreb index: M2(G) uvE(G)i(Δ(u)×Δ(v)) (Dx×Dy)(z(x,y))x=y=1 44
Nbd 2nd zagreb index: NM2(G)
2nd modified Zagreb index: mM2(G) uvE(G)i1Δ(u)Δ(v) (SxSy)(z(x,y))x=y=1 45
Nbd 2nd modified zagreb index: NmM2(G)
Redefined 3rd Zagreb index: ReZG3(G) uvE(G)i[Δ(u)Δ(v)×(Δ(u)+Δ(v))] DxDy(Dx+Dy)(z(x,y))x=y=1 46,47
3rd Nde index: ND3(G)
Forgotten topological index: F(G) uvE(G)i(Δ2(u)+Δ2(v)) (Dx2+Dy2)(z(x,y))x=y=1 48
Nbd Forgotten topological index: NF(G)
Randic index: Rα(G) uvE(G)i(Δ(u)Δ(v))α (DxαDyα)(z(x,y))x=y=1 49
Nbd Randic index: NRα(G)
Inverse Randic index: RRα(G) uvE(G)i1(Δ(u)Δ(v))α (SxαSyα)(z(x,y))x=y=1 50
Nbd inverse Randic index: NRRα(G)
Symmetric Division index: SDD(G) uvE(G)iΔ2(u)+Δ2(v)Δ(u)Δ(v) (DxSy+SxDy)(z(x,y))x=y=1 51
Fifth NDe index: ND5(G)
Harmonic index: H(G) uvE(G)i2Δ(u)+Δ(v) (2SxJ)(z(x,y))x=1 52
Nbd Harmonic index: NH(G)
Inverse sum indeg index: I(G) uvE(G)iΔ(u)Δ(v)Δ(u)+Δ(v) (SxJDxDy)(z(x,y))x=1 51
Nbd Inverse sum indeg index: NI(G)
Augmented Zagreb index: A(G) uvE(G)i{Δ(u)Δ(v)Δ(u)+Δ(v)-2}3 (Sx3Q-2JDx3Dy3)(z(x,y))x=1 53,54
Sanskurti index: S(G)