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A024434
Expansion of 1/((1-x)(1-6x)(1-10x)(1-11x)).
1
1, 28, 521, 8120, 114765, 1526196, 19481953, 241575376, 2932083605, 35012557580, 412807072041, 4818002535528, 55771887460381, 641245030592740, 7331332058802545, 83421584091633536, 945410124787913253
OFFSET
0,2
FORMULA
a(n)=(18*11^(n+3) - 25*10^(n+3) + 9*6^(n+3) - 2)/900. [Yahia Kahloune, Jun 27 2013]
a(0)=1, a(1)=28, a(2)=521, a(3)=8120; for n>3, a(n) = 28*a(n-1) -263*a(n-2) +896*a(n-3)-660*a(n-4). - Vincenzo Librandi, Jul 16 2013
MATHEMATICA
CoefficientList[Series[1 / ((1 - x) (1 - 6 x) (1 - 10 x) (1 - 11 x)), {x, 0, 20}], x] (* Vincenzo Librandi, Jul 16 2013 *)
LinearRecurrence[{28, -263, 896, -660}, {1, 28, 521, 8120}, 20] (* Harvey P. Dale, Mar 31 2018 *)
PROG
(Magma) m:=25; R<x>:=PowerSeriesRing(Integers(), m); Coefficients(R!(1/((1-x)*(1-6*x)*(1-10*x)*(1-11*x)))); /* or */ I:=[1, 28, 521, 8120]; [n le 4 select I[n] else 28*Self(n-1)-263*Self(n-2)+896*Self(n-3)-660*Self(n-4): n in [1..25]]; // Vincenzo Librandi, Jul 16 2013
CROSSREFS
Sequence in context: A283244 A024442 A026108 * A024440 A024347 A025984
KEYWORD
nonn,easy
AUTHOR
STATUS
approved