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A169832
a(n) = 15*2^(n+1) - (5*n^2+22*n+30).
1
0, 3, 26, 99, 282, 695, 1578, 3411, 7154, 14727, 29970, 60563, 121866, 244599, 490202, 981555, 1964418, 3930311, 7862274, 15726387, 31454810, 62911863, 125826186, 251655059, 503313042, 1006629255, 2013261938, 4026527571, 8053059114, 16106122487, 32212249530
OFFSET
0,2
LINKS
B. Berselli, Table of n, a(n) for n = 0..1000 [From Bruno Berselli, Jun 03 2010]
P. Nissen and J. Taylor, Running clubs - a combinatorial investigation, Math. Mag., 64 (No. 1, 1991), 39-44.
FORMULA
From Bruno Berselli and R. J. Mathar, Jun 03 2010: (Start)
G.f.: x*(3+11*x-4*x^2)/[(1-2*x)*(1-x)^3].
a(n) - 5*a(n-1) + 9*a(n-2) - 7*a(n-3) + 2*a(n-4) = 0, with n>3. (End)
MATHEMATICA
LinearRecurrence[{5, -9, 7, -2}, {0, 3, 26, 99}, 40] (* Harvey P. Dale, Sep 24 2014 *)
CROSSREFS
Sequence in context: A292001 A211622 A062124 * A322300 A100606 A307918
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Jun 01 2010
STATUS
approved