OFFSET
1,2
COMMENTS
The length of each row is 5.
The minimal polynomial of (2*cos(Pi/15))^n, for n >= 1, is C(15, n, x) = Product_{j=0..3} (x - (x_j)^n) = Sum_{k=0} T(n, k) x^k, where x_0 = 2*cos(Pi/15), x_1 = 2*cos(7*Pi/15), x_2 = 2*cos(11*Pi/15), and x_3 = 2*cos(13*Pi/15) are the zeros of C(15, 1, x) with coefficients given in A187360 (row n=15).
FORMULA
EXAMPLE
The rectangular array T(n, k) begins:
n\k 0 1 2 3 4
---------------------------------
1: 1 -4 -4 1 1
2: 1 -24 26 -9 1
3: 1 -109 -49 1 1
4: 1 -524 246 -29 1
5: 1 -2504 -619 -4 1
6: 1 -11979 2621 -99 1
7: 1 -57299 -7774 -34 1
...
MATHEMATICA
Flatten[Table[CoefficientList[MinimalPolynomial[(2*Cos[\[Pi]/15])^n, x], x], {n, 1, 15}]]
CROSSREFS
KEYWORD
sign,tabf,easy
AUTHOR
Greg Dresden and Wolfdieter Lang, May 02 2019
STATUS
approved