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A192829 Molecular topological indices of the n X n X n grid graphs. 1
360, 8064, 68928, 355470, 1340424, 4086180, 10680384, 24847938, 52769640, 104137704, 193478400, 341772054, 578400648, 943453260, 1490419584, 2289301770, 3430174824, 5027225808, 7223302080, 10194998814, 14158316040, 19374915444, 26159007168, 34884896850, 45995223144, 60009915960, 77535905664, 99277613478, 126048253320 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,1

LINKS

G. C. Greubel, Table of n, a(n) for n = 2..1000

Eric Weisstein's World of Mathematics, Grid Graph

Eric Weisstein's World of Mathematics, Molecular Topological Index

Index entries for linear recurrences with constant coefficients, signature (8,-28,56,-70,56,-28,8,-1).

FORMULA

a(n) = n*(24-66*n+36*n^2+4*n^3-3*n^4-7*n^5+6*n^6).

G.f.: 6*x^2*(60+864*x+2416*x^2+1613*x^3+44*x^4+50*x^5-8*x^6+x^7)/(1-x)^8. - Colin Barker, Aug 07 2012

E.g.f.: x*(6 +(-6 +186*x +1161*x^2 +1619*x^3 +732*x^4 +119*x^5+6*x^6)* exp(x)). - G. C. Greubel, Jan 04 2019

MATHEMATICA

Table[n*(24-66*n+36*n^2+4*n^3-3*n^4-7*n^5+6*n^6), {n, 2, 40}] (* G. C. Greubel, Jan 04 2019 *)

PROG

(PARI) vector(40, n, n++; n*(24-66*n+36*n^2+4*n^3-3*n^4-7*n^5+6*n^6)) \\ G. C. Greubel, Jan 04 2019

(MAGMA) [n*(24-66*n+36*n^2+4*n^3-3*n^4-7*n^5+6*n^6): n in [2..40]]; // G. C. Greubel, Jan 04 2019

(Sage) [n*(24-66*n+36*n^2+4*n^3-3*n^4-7*n^5+6*n^6) for n in (2..40)] # G. C. Greubel, Jan 04 2019

(GAP) List([2..40], n -> n*(24-66*n+36*n^2+4*n^3-3*n^4-7*n^5+6*n^6)); # G. C. Greubel, Jan 04 2019

CROSSREFS

Sequence in context: A305626 A056322 A056313 * A229681 A054648 A230684

Adjacent sequences:  A192826 A192827 A192828 * A192830 A192831 A192832

KEYWORD

nonn,easy

AUTHOR

Eric W. Weisstein, Jul 11 2011

STATUS

approved

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Last modified September 27 03:21 EDT 2020. Contains 337380 sequences. (Running on oeis4.)