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A179980
a(n) = 10*a(n-1) - (-1)^n * n, a(1) = 1.
0
1, 8, 83, 826, 8265, 82644, 826447, 8264462, 82644629, 826446280, 8264462811, 82644628098, 826446280993, 8264462809916, 82644628099175, 826446280991734, 8264462809917357, 82644628099173552, 826446280991735539, 8264462809917355370, 82644628099173553721
OFFSET
1,2
FORMULA
From R. J. Mathar, Aug 06 2010: (Start)
a(n) = +8*a(n-1) +19*a(n-2) +10*a(n-3).
G.f.: -x/((10*x-1)*(1+x)^2).
a(n) = (10^(n+1) -11*n*(-1)^n -10*(-1)^n)/121. (End)
MATHEMATICA
LinearRecurrence[{8, 19, 10}, {1, 8, 83}, 20] (* Harvey P. Dale, Nov 17 2014 *)
CROSSREFS
Sequence in context: A069620 A196482 A196715 * A236671 A232226 A238811
KEYWORD
nonn,easy
AUTHOR
Mark Dols, Aug 04 2010
STATUS
approved