OFFSET
1,2
LINKS
Colin Barker,Table of n, a(n) for n = 1..1000
Eric Weisstein's World of Mathematics,Molecular Topological Index
Eric Weisstein's World of Mathematics,Mycielski Graph
Index entries for linear recurrences with constant coefficients,signature (16,-95,260,-324,144).
FORMULA
a(n) = (3*2^n - 8)*(18 - 27*2^n + 14*3^n)/36, n > 1, with a(1)=0.
G.f.: 4*x^2*(12*x^4 - 2*x^3 + 25*x^2 - 4*x - 1)/((x-1)*(2*x-1)*(3*x-1)*(4*x-1)*(6*x-1)). -Colin Barker,Aug 07 2012
E.g.f.: (25 + 12*x - 144*exp(x) + 270*exp(2*x) - 112*exp(3*x) - 81*exp(4*x) + 42*exp(6*x))/36. -G. C. Greubel,Jan 04 2019
MAPLE
0, seq((3*2^n-8)*(18-27*2^n+14*3^n)/36, n=2..25); #Muniru A Asiru,Jan 05 2019
MATHEMATICA
Table[If[n==1, 0, (3*2^n-8)*(18-27*2^n+14*3^n)/36], {n, 1, 30}]
PROG
(PARI) concat(0, Vec(4*x^2*(12*x^4-2*x^3+25*x^2-4*x-1)/((x-1)*(2*x-1)*(3*x-1)*(4*x-1)*(6*x-1)) + O(x^30))) \\Colin Barker,Oct 14 2017
(PARI) vector(30, n, if(n==1, 0, (3*2^n-8)*(18-27*2^n+14*3^n)/36)) \\G. C. Greubel,Jan 04 2019
(Magma) [0] cat [(3*2^n-8)*(18-27*2^n+14*3^n)/36: n in [2..30]]; //G. C. Greubel,Jan 04 2019
(Sage) [0] + [(3*2^n-8)*(18-27*2^n+14*3^n)/36 for n in (2..30)] #G. C. Greubel,Jan 04 2019
(GAP) Concatenation([0], List([2..30], n -> (3*2^n-8)*(18-27*2^n+ 14*3^n)/36)); #G. C. Greubel,Jan 04 2019
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Eric W. Weisstein,Jul 11 2011
STATUS
approved