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A063704
Cyclotomic polynomials Phi_n at x=phi divided by sqrt(5) and floored down (where phi = tau = (sqrt(5)+1)/2).
5
0, 0, 1, 2, 1, 7, 0, 20, 3, 10, 2, 143, 2, 376, 5, 11, 21, 2583, 6, 6764, 15, 74, 34, 46367, 18, 7435, 89, 2618, 104, 832039, 25, 2178308, 987, 3399, 610, 20160, 136, 39088168, 1597, 23228, 861, 267914295, 182, 701408732, 4895, 35920, 10946, 4807526975
OFFSET
0,4
MAPLE
with(numtheory); Phi_at_x := (n, y) -> subs(x=y, cyclotomic(n, x)); [seq(floor(evalf(simplify(Phi_at_x(j, (sqrt(5)+1)/2))/(sqrt(5)))), j=0..120)];
MATHEMATICA
Floor[Simplify[Cyclotomic[Range[0, 50], GoldenRatio]]/Sqrt[5]] (* Paolo Xausa, Feb 27 2024 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Antti Karttunen, Aug 03 2001
EXTENSIONS
a(47) corrected by Sean A. Irvine, May 08 2023
STATUS
approved