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A349811
Table of triples read by rows: the fundamental unit of the purely real cubic field Q(m^(1/3)), m = A349810(n), is (T(n,0) + T(n,1)*x + T(n,2)*x^2)/d, where x = m^(1/3) and d is a small integer, usually 1.
1
1, 1, 1, 4, 3, 2, 41, 24, 14, 109, 60, 33, 4, 2, 1, 23, 11, 5, 89, 40, 18, 110, 48, 21, 94, 40, 17, 29, 12, 5, 5401, 2190, 888, 324, 126, 49, 14, 5, 2, 22, 8, 3, 1705, 618, 224, 793, 283, 101, 2166673601, 761875860, 267901370
OFFSET
1,4
COMMENTS
The denominator d is 1 with the following exceptions: 3 for m=10, 2 for m=12, 3 for m=19, 2 for m=20, and so on.
Wada's table extends to m=249.
LINKS
Hideo Wada, A table of fundamental units of purely cubic fields, Proc. Japan Acad. 46 (1970), 1135-1140. [Math. Rev. MR0294292]
EXAMPLE
The table begins as follows (the denominator d has been included if it is not 1, and m = A349810(n)):
n m (T(n,0) T(n,1) T(n,2))/d
1 2 1, 1, 1,
2 3 4, 3, 2,
3 5 41, 24, 14,
4 6 109, 60, 33,
5 7 4, 2, 1,
6 10 (23, 11, 5)/3,
7 11 89, 40, 18,
8 12 (110, 48, 21)/2,
9 13 94, 40, 17,
10 14 29, 12, 5,
11 15 5401, 2190, 888,
12 17 324, 126, 49,
13 19 (14, 5, 2)/3,
14 20 (22, 8, 3)/2,
15 21 1705, 618, 224,
16 22 793, 283, 101,
17 23 2166673601, 761875860, 267901370,
...
CROSSREFS
Cf. A349810.
Sequence in context: A019130 A245348 A174551 * A239799 A305235 A120011
KEYWORD
nonn,tabf
AUTHOR
N. J. A. Sloane, Dec 22 2021
STATUS
approved