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A024108
a(n) = 9^n-n^7.
2
1, 8, -47, -1458, -9823, -19076, 251505, 3959426, 40949569, 382637520, 3476784401, 31361572438, 282393704673, 2541803079812, 22876687041457, 205890961235274, 1853019920416385, 16677181289327896, 150094634684779089, 1350851716779120350
OFFSET
0,2
LINKS
Index entries for linear recurrences with constant coefficients, signature (17,-100,308,-574,686,-532,260,-73,9).
FORMULA
G.f.: -(10*x^8+1071*x^7+10627*x^6+20497*x^5+8373*x^4-167*x^3-83*x^2-9*x+1) / ((x-1)^8*(9*x-1)). - Colin Barker, Mar 20 2015
a(n) = A001019(n) - A001015(n). - Michel Marcus, Mar 20 2015
MATHEMATICA
Table[9^n - n^7, {n, 0, 19}] (* Michael De Vlieger, Mar 20 2015 *)
LinearRecurrence[{17, -100, 308, -574, 686, -532, 260, -73, 9}, {1, 8, -47, -1458, -9823, -19076, 251505, 3959426, 40949569}, 20] (* Harvey P. Dale, Mar 23 2018 *)
PROG
(Magma) [9^n-n^7: n in [0..25]]; // Vincenzo Librandi, Jul 06 2011
(PARI) Vec(-(10*x^8+1071*x^7+10627*x^6+20497*x^5+8373*x^4-167*x^3-83*x^2-9*x+1)/((x-1)^8*(9*x-1)) + O(x^100)) \\ Colin Barker, Mar 20 2015
CROSSREFS
Sequence in context: A054488 A034349 A296797 * A247726 A263506 A216323
KEYWORD
sign,easy
STATUS
approved