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A182466
a(n) = 3a(n-1) - 2a(n-2) with a(0)=32 and a(1)=80.
6
32, 80, 176, 368, 752, 1520, 3056, 6128, 12272, 24560, 49136, 98288, 196592, 393200, 786416, 1572848, 3145712, 6291440, 12582896, 25165808, 50331632, 100663280, 201326576, 402653168, 805306352, 1610612720, 3221225456, 6442450928, 12884901872, 25769803760, 51539607536
OFFSET
0,1
COMMENTS
Number of vertices into building blocks of 3d objects with 8 vertices.
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 *)
KEYWORD
nonn,easy
AUTHOR
Odimar Fabeny, Apr 30 2012
STATUS
approved