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A198771
(11*5^n-1)/2.
1
5, 27, 137, 687, 3437, 17187, 85937, 429687, 2148437, 10742187, 53710937, 268554687, 1342773437, 6713867187, 33569335937, 167846679687, 839233398437, 4196166992187, 20980834960937, 104904174804687, 524520874023437, 2622604370117187
OFFSET
0,1
FORMULA
a(n) = 5*a(n-1)+2. a(n) = 6*a(n-1)-5*a(n-2), n>1.
G.f. ( 5-3*x ) / ( (5*x-1)*(x-1) ). - R. J. Mathar, Oct 30 2011
MATHEMATICA
(11*5^Range[0, 30]-1)/2 (* or *) LinearRecurrence[{6, -5}, {5, 27}, 30] (* Harvey P. Dale, Mar 30 2024 *)
PROG
(Magma) [(11*5^n-1)/2: n in [0..30]]
CROSSREFS
Sequence in context: A009027 A275540 A037498 * A084177 A037675 A221673
KEYWORD
nonn,easy
AUTHOR
Vincenzo Librandi, Oct 30 2011
STATUS
approved