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A021614
Expansion of 1/((1-x)*(1-3*x)*(1-7*x)*(1-11*x)).
1
1, 22, 332, 4322, 52353, 609924, 6948544, 78112924, 871004585, 9663416906, 106874239836, 1179653481006, 13004446987897, 143246730136168, 1577098731557408, 17357778969071768, 191003419177941489, 2101512564778130910, 23119962889885992460, 254342864531775176410, 2797934419055961932561
OFFSET
0,2
FORMULA
a(0)=1, a(1)=22, a(2)=332, a(3)=4322; for n>3, a(n) = 22*a(n-1) -152*a(n-2) +362*a(n-3) -231*a(n-4). - Vincenzo Librandi, Jul 11 2013
MATHEMATICA
CoefficientList[Series[1 / ((1 - x) (1 - 3 x) (1 - 7 x) (1 - 11 x)), {x, 0, 20}], x] (* Vincenzo Librandi, Jul 11 2013 *)
PROG
(Magma) m:=25; R<x>:=PowerSeriesRing(Integers(), m); Coefficients(R!(1/((1-x)*(1-3*x)*(1-7*x)*(1-11*x)))); // Vincenzo Librandi, Jul 11 2013
(Magma) I:=[1, 22, 332, 4322]; [n le 4 select I[n] else 22*Self(n-1)-152*Self(n-2)+362*Self(n-3)-231*Self(n-4): n in [1..25]]; // Vincenzo Librandi, Jul 11 2013
CROSSREFS
Sequence in context: A021644 A021834 A019671 * A258006 A309654 A019854
KEYWORD
nonn,easy
STATUS
approved