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A024080
a(n) = 7^n - n^5.
2
1, 6, 17, 100, 1377, 13682, 109873, 806736, 5732033, 40294558, 282375249, 1977165692, 13841038369, 96888639114, 678222535025, 4747560750568, 33232929521025, 232630512567350, 1628413596020881, 11398895182897044
OFFSET
0,2
LINKS
FORMULA
From Chai Wah Wu, Jul 10 2016: (Start)
a(n) = 13*a(n-1) - 57*a(n-2) + 125*a(n-3) - 155*a(n-4) + 111*a(n-5) - 43*a(n-6) + 7*a(n-7) for n > 6.
G.f.: (-8*x^6 - 175*x^5 - 451*x^4 - 96*x^3 + 4*x^2 + 7*x - 1)/((x - 1)^6*(7*x - 1)). (End)
PROG
(Magma) [7^n-n^5: n in [0..25]]; // Vincenzo Librandi, Jul 03 2011
CROSSREFS
Sequence in context: A338747 A154494 A130278 * A099436 A209482 A209341
KEYWORD
nonn,easy
STATUS
approved