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A173785
Expansion of 2*(1 -4*x +14*x^2 +4*x^3 +9*x^4)/(1-x)^5.
1
2, 2, 18, 98, 338, 882, 1922, 3698, 6498, 10658, 16562, 24642, 35378, 49298, 66978, 89042, 116162, 149058, 188498, 235298, 290322, 354482, 428738, 514098, 611618, 722402, 847602, 988418, 1146098, 1321938, 1517282, 1733522, 1972098, 2234498
OFFSET
0,1
REFERENCES
Clark Kimberling, Complementary Equations, Journal of Integer Sequences, Vol. 10 (2007), Article 07.1.4.
LINKS
Clark Kimberling, Complementary Equations, Journal of Integer Sequences, Vol. 10 (2007), Article 07.1.4.
FORMULA
G.f.: 2*(1 -4*x +14*x^2 +4*x^3 +9*x^4)/(1-x)^5.
a(n) = 2*(n^2 - n + 1)^2.
a(n) = 2*A058031(n).
E.g.f.: 2*(1 + 4*x^2 + 4*x^3 + x^4)*exp(x). - G. C. Greubel, Jul 07 2021
MAPLE
a:= n-> 2*(n^2-n+1)^2:
seq (a(n), n=0..40);
MATHEMATICA
Table[2*(1-n+n^2)^2, {n, 0, 40}] (* G. C. Greubel, Jul 07 2021 *)
LinearRecurrence[{5, -10, 10, -5, 1}, {2, 2, 18, 98, 338}, 50] (* Harvey P. Dale, Apr 20 2024 *)
PROG
(SageMath) [2*(1-n+n^2)^2 for n in (0..40)] # G. C. Greubel, Jul 07 2021
(PARI) a(n)=2*(n^2-n+1)^2 \\ Charles R Greathouse IV, Oct 21 2022
CROSSREFS
Cf. A058031.
Sequence in context: A121670 A001183 A201124 * A264715 A294341 A318418
KEYWORD
nonn,easy
AUTHOR
Michel Lagneau, Feb 24 2010
EXTENSIONS
Edited by Alois P. Heinz, Feb 16 2012
STATUS
approved