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A192839 Molecular topological indices of the square graphs. 1
0, 48, 768, 4320, 15360, 42000, 96768, 197568, 368640, 641520, 1056000, 1661088, 2515968, 3690960, 5268480, 7344000, 10027008, 13441968, 17729280, 23046240, 29568000, 37488528, 47021568, 58401600, 71884800, 87750000, 106299648, 127860768, 152785920, 181454160 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

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 (6,-15,20,-15,6,-1).

FORMULA

a(n) = 8*n*(n+1)*(n-1)^3.

G.f.: 48*x^2*(1+x)*(1+9*x)/(1-x)^6. - Colin Barker, Aug 07 2012

E.g.f.: 8*x^2*(3 + 13*x + 8*x^2 + x^3)*exp(x). - G. C. Greubel, Jan 04 2019

MAPLE

[8*n*(n+1)*(n-1)^3$n=1..30]; # Muniru A Asiru, Jan 05 2019

MATHEMATICA

Table[, {n, 1, 30}] (* G. C. Greubel, Jan 04 2019 *)

PROG

(PARI) vector(30, n, 8*n*(n+1)*(n-1)^3) \\ G. C. Greubel, Jan 04 2019

(MAGMA) [8*n*(n+1)*(n-1)^3: n in [1..30]]; // G. C. Greubel, Jan 04 2019

(Sage) [8*n*(n+1)*(n-1)^3 for n in (1..30)] # G. C. Greubel, Jan 04 2019

(GAP) List([1..30], n -> 8*n*(n+1)*(n-1)^3); # G. C. Greubel, Jan 04 2019

CROSSREFS

Sequence in context: A132464 A145155 A105948 * A014401 A241873 A233784

Adjacent sequences:  A192836 A192837 A192838 * A192840 A192841 A192842

KEYWORD

nonn,easy

AUTHOR

Eric W. Weisstein, Jul 11 2011

STATUS

approved

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Last modified January 19 23:25 EST 2019. Contains 319319 sequences. (Running on oeis4.)