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A074517
a(n) = 1^n + 5^n + 7^n.
0
3, 13, 75, 469, 3027, 19933, 133275, 901669, 6155427, 42306733, 292240875, 2026154869, 14085427827, 98109713533, 684326588475, 4778079088069, 33385518460227, 233393453440333, 1632228295176075, 11417968671701269
OFFSET
0,1
FORMULA
From Mohammad K. Azarian, Dec 26 2008: (Start)
G.f.: 1/(1-x) + 1/(1-5*x) + 1/(1-7*x).
E.g.f.: e^x + e^(5*x)*e^(7*x). (End)
a(n) = 12*a(n-1) - 35*a(n-2) + 24 with a(0)=3, a(1)=13. - Vincenzo Librandi, Jul 21 2010
a(0)=3, a(1)=13, a(2)=75, a(n) = 13*a(n-1) - 47*a(n-2) + 35*a(n-3). - Harvey P. Dale, Apr 15 2015
MATHEMATICA
Table[1^n + 5^n + 7^n, {n, 0, 20}]
LinearRecurrence[{13, -47, 35}, {3, 13, 75}, 30] (* Harvey P. Dale, Apr 15 2015 *)
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Robert G. Wilson v, Aug 23 2002
STATUS
approved