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A054327
Ninth column of Lanczos triangle A053125 (decreasing powers).
2
9, 660, 20592, 411840, 6223360, 77395968, 833495040, 8033304576, 70882099200, 581979340800, 4500640235520, 33087710822400, 232937484189696, 1579462143508480, 10363761453957120, 66060621396836352, 410376587465195520, 2491227283906363392, 14812702769172971520, 86437418048453345280
OFFSET
0,1
REFERENCES
Cornelius Lanczos, Applied Analysis, Prentice-Hall, Englewood Cliffs, NJ, 1956, p. 518.
Theodore J. Rivlin, Chebyshev polynomials: from approximation theory to algebra and number theory, 2nd ed., Wiley, New York, 1990.
FORMULA
a(n) = 4^n*binomial(2*n+9, 8) = A053125(n+8, 8).
G.f.: (4*x+3)*(64*x^3+528*x^2+108*x+3)/(1-4*x)^9.
From Amiram Eldar, Oct 30 2025: (Start)
Sum_{n>=0} 1/a(n) = 298184/21 + 34976*log(2) - 34992*log(3).
Sum_{n>=0} (-1)^n/a(n) = -443944/105 + 8896*arctan(1/2) + 464*log(5/4). (End)
MATHEMATICA
Table[4^n*Binomial[2*n+9, 8], {n, 0, 20}] (* G. C. Greubel, Jul 22 2019 *)
PROG
(PARI) vector(20, n, n--; 4^n*binomial(2*n+9, 8)) \\ G. C. Greubel, Jul 22 2019
(Magma) [4^n*Binomial(2*n+9, 8): n in [0..20]]; // G. C. Greubel, Jul 22 2019
(SageMath) [4^n*binomial(2*n+9, 8) for n in (0..20)] # G. C. Greubel, Jul 22 2019
(GAP) List([0..20], n-> 4^n*Binomial(2*n+9, 8)); # G. C. Greubel, Jul 22 2019
CROSSREFS
Sequence in context: A091062 A221133 A015007 * A209964 A287937 A372184
KEYWORD
nonn,easy
STATUS
approved