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A298078
a(n) = 7*n^2 - 7*n - 43.
2
-43, -29, -1, 41, 97, 167, 251, 349, 461, 587, 727, 881, 1049, 1231, 1427, 1637, 1861, 2099, 2351, 2617, 2897, 3191, 3499, 3821, 4157, 4507, 4871, 5249, 5641, 6047, 6467, 6901, 7349, 7811, 8287, 8777, 9281, 9799, 10331, 10877, 11437, 12011, 12599, 13201, 13817, 14447, 15091, 15749, 16421, 17107
OFFSET
1,1
FORMULA
From Colin Barker, Jan 14 2018: (Start)
G.f.: -x*(43 - 100*x + 43*x^2) / (1 - x)^3.
a(n) = 3*a(n-1) - 3*a(n-2) + a(n-3) for n>3. (End)
E.g.f.: 43 + exp(x)*(-43 + 7*x^2). - Stefano Spezia, Oct 17 2019
MATHEMATICA
Array[7 #^2 - 7 # - 43 &, 48] (* Michael De Vlieger, Jan 11 2018 *)
LinearRecurrence[{3, -3, 1}, {-43, -29, -1}, 50] (* Harvey P. Dale, Jul 05 2021 *)
PROG
(PARI) Vec(-x*(43 - 100*x + 43*x^2) / (1 - x)^3 + O(x^60)) \\ Colin Barker, Jan 14 2018
CROSSREFS
Cf. A272077.
Sequence in context: A033363 A187088 A127147 * A291494 A051614 A291479
KEYWORD
sign,easy
AUTHOR
Charles Kusniec, Jan 11 2018
STATUS
approved