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A128784
n^2*5^n.
1
0, 5, 100, 1125, 10000, 78125, 562500, 3828125, 25000000, 158203125, 976562500, 5908203125, 35156250000, 206298828125, 1196289062500, 6866455078125, 39062500000000, 220489501953125, 1235961914062500, 6885528564453125
OFFSET
0,2
FORMULA
a(0)=0, a(1)=5, a(2)=100, a(n)=15*a(n-1)-75*a(n-2)+125*a(n-3) [From Harvey P. Dale, Dec 30 2011]
G.f.: -5*(5*x^2+x)/(5*x-1)^3. - Harvey P. Dale, Dec 30 2011
MATHEMATICA
Table[n^2 5^n, {n, 0, 20}] (* or *) LinearRecurrence[{15, -75, 125}, {0, 5, 100}, 20] (* Harvey P. Dale, Dec 30 2011 *)
PROG
(PARI) a(n)=n^2*5^n \\ Charles R Greathouse IV, May 16 2018
CROSSREFS
Sequence in context: A156276 A322715 A208348 * A369535 A078534 A141120
KEYWORD
nonn,easy
AUTHOR
Mohammad K. Azarian, Apr 07 2007
STATUS
approved