OFFSET
0,1
COMMENTS
Number of vertices into building blocks of 3d objects with 8 vertices.
LINKS
Harvey P. Dale, Table of n, a(n) for n = 0..1000
Index entries for linear recurrences with constant coefficients, signature (3, -2).
FORMULA
a(n) = a(n-1)*2 + 16.
a(n) = 8*(3*2^n-2). - Harvey P. Dale, Aug 23 2012
G.f.: -((16(x-2))/(2*x^2-3*x+1)). - Harvey P. Dale, Aug 23 2012
EXAMPLE
a(0) = 8+16+8;
a(1) = 8+16+32+16+8;
a(2) = 8+16+32+64+32+16+8;
a(3) = 8+16+32+64+128+64+32+16+8.
MATHEMATICA
LinearRecurrence[{3, -2}, {32, 80}, 40] (* or *) Table[8(3*2^n-2), {n, 40}] (* Harvey P. Dale, Aug 23 2012 *)
CoefficientList[Series[-((16 (x - 2))/(2 x^2 - 3 x + 1)), {x, 0, 40}], x] (* Vincenzo Librandi, Jun 02 2014 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Odimar Fabeny, Apr 30 2012
STATUS
approved