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A253210
a(n) = 7^n + 6.
2
7, 13, 55, 349, 2407, 16813, 117655, 823549, 5764807, 40353613, 282475255, 1977326749, 13841287207, 96889010413, 678223072855, 4747561509949, 33232930569607, 232630513987213, 1628413597910455, 11398895185373149, 79792266297612007, 558545864083284013
OFFSET
0,1
COMMENTS
Subsequence of A226819.
FORMULA
G.f.: (7 - 43*x) / ((1 - x)*(1 - 7*x)).
a(n) = 8*a(n-1) - 7*a(n-2) for n>1.
MATHEMATICA
Table[7^n + 6, {n, 0, 30}]
PROG
(Magma) [7^n+6: n in [0..30]];
CROSSREFS
Cf. similar sequences listed in A253208.
Sequence in context: A091005 A015441 A255286 * A183180 A133664 A143794
KEYWORD
nonn,easy
AUTHOR
Vincenzo Librandi, Dec 29 2014
STATUS
approved