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A025963
Expansion of 1/((1-2*x)*(1-4*x)*(1-5*x)*(1-11*x)).
1
1, 22, 325, 4110, 48381, 550062, 6148165, 68149870, 752379661, 8290355502, 91266902805, 1004309278830, 11049302357341, 121551961591342, 1337120292662245, 14708568942522990, 161795495573813421, 1779756671701857582, 19577354628108674485, 215351057655891914350
OFFSET
0,2
FORMULA
a(n) = -4*2^n/27+32*4^n/7-125*5^n/18+1331*11^n/378. - R. J. Mathar, Jun 20 2013
a(n) = (4^(n+1)-2^(n+1))/2+16*a(n-1)-55*a(n-2). - Vincenzo Librandi, Jun 04 2026
MATHEMATICA
CoefficientList[Series[1/((1-2*x)*(1-4*x)*(1-5*x)*(1-11*x)), {x, 0, 30}], x] (* Harvey P. Dale, Jul 16 2016 *)
(* Alternative: *)
LinearRecurrence[{22, -159, 458, -440}, {1, 22, 325, 4110}, 30] (* Harvey P. Dale, Jul 16 2016 *)
(* Alternative: *)
a[0]=1; a[1]=22; Do[a[n]=(4^(n+1)-2^(n+1))/2+16*a[n-1]-55*a[n-2], {n, 2, 22}]; Table[a[n], {n, 0, 22}] (* Vincenzo Librandi, Jun 04 2026 *)
PROG
(Magma) I:=[1, 22]; [n le 2 select I[n] else (4^n-2^n)/2+16*Self(n-1)-55*Self(n-2): n in [1..22]]; // Vincenzo Librandi, Jun 04 2026
CROSSREFS
Sequence in context: A288576 A020571 A021874 * A020343 A025941 A125479
KEYWORD
nonn,easy,changed
EXTENSIONS
More terms from Vincenzo Librandi, Jun 04 2026
STATUS
approved