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A074568
a(n) = 4^n + 7^n + 8^n.
1
3, 19, 129, 919, 6753, 50599, 383889, 2937079, 22607553, 174833479, 1357265649, 10571455639, 82577541153, 646711933159, 5076538019409, 39933007340599, 314712202247553, 2484447507541639, 19642880826869169, 155514358139135959
OFFSET
0,1
FORMULA
From Mohammad K. Azarian, Dec 30 2008: (Start)
G.f.: 1/(1-4*x) + 1/(1-7*x) + 1/(1-8*x).
E.g.f.: exp(4*x) + exp(7*x) + exp(8*x). (End)
a(n) = 19*a(n-1) - 116*a(n-2) + 224*a(n-3). - Wesley Ivan Hurt, Apr 19 2021
MATHEMATICA
Table[4^n + 7^n + 8^n, {n, 0, 20}]
LinearRecurrence[{19, -116, 224}, {3, 19, 129}, 20] (* Harvey P. Dale, Aug 15 2016 *)
PROG
(Magma) [4^n + 7^n + 8^n: n in [0..20]]; // Vincenzo Librandi, Aug 14 2011
(PARI) vector(20, n, n--; 4^n + 7^n + 8^n) \\ G. C. Greubel, Nov 08 2018
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Robert G. Wilson v, Aug 23 2002
STATUS
approved