OFFSET
1,1
LINKS
Paolo Xausa, Table of n, a(n) for n = 1..1000
John C. Baez, Motivating Motives, arXiv:2304.08737 [math.NT], 2023. See pp. 4-5.
Index entries for linear recurrences with constant coefficients, signature (0,2,4).
FORMULA
a(n) = 4 * A038518(n). - Joerg Arndt, Apr 20 2023
From Stefano Spezia, May 28 2024: (Start)
G.f.: 4*x*(1 + x - x^2)/((1 - 2*x)*(1 + 2*x + 2*x^2)).
E.g.f.: 2*cosh(x)*(cosh(x) - cos(x)) + 2*(cosh(x) + cos(x))*sinh(x). (End)
MATHEMATICA
LinearRecurrence[{0, 2, 4}, {4, 4, 4}, 50] (* Paolo Xausa, May 28 2024 *)
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Michel Marcus, Apr 20 2023
STATUS
approved