login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A278564 Irregular triangle read by rows: row n lists (negated) determinants of the quadratic Farey series of order n. 0
1, 1, 3, 1, 1, 2, 3, 2, 1, 1, 2, 3, 1, 5, 1, 3, 2, 1, 1, 2, 2, 3, 2, 5, 2, 3, 2, 2, 1, 1, 2, 2, 3, 1, 4, 2, 1, 7, 1, 2, 4, 1, 3, 2, 2, 1, 1, 2, 2, 2, 3, 1, 5, 1, 2, 1, 7, 1, 2, 1, 5, 1, 3, 2, 2, 2, 1, 1, 2, 2, 2, 3, 1, 4, 2, 5, 2, 3, 1, 1, 9, 1, 1, 3, 2, 5, 2, 4, 1, 3, 1, 1, 1, 1, 1, 2, 2, 2, 2, 3, 1, 4, 2, 1, 6, 2, 3, 2, 1, 9, 1, 2, 3, 2, 6, 1, 1, 2, 4, 1, 3, 2, 2, 2, 2, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET

2,3

LINKS

Table of n, a(n) for n=2..127.

H. Brown, K. Mahler, A generalization of Farey sequences: Some exploration via the computer, Journal of Number Theory 3.3 (1971): 364-370.

EXAMPLE

Triangle begins:

1,

1,3,1,

1,2,3,2,1,

1,2,3,1,5,1,3,2,1,

1,2,2,3,2,5,2,3,2,2,1,

1,2,2,3,1,4,2,1,7,1,2,4,1,3,2,2,1,

1,2,2,2,3,1,5,1,2,1,7,1,2,1,5,1,3,2,2,2,1,

1,2,2,2,3,1,4,2,5,2,3,1,1,9,1,1,3,2,5,2,4,1,3,1,1,1,1,

1,2,2,2,2,3,1,4,2,1,6,2,3,2,1,9,1,2,3,2,6,1,1,2,4,1,3,2,2,2,2,1,

...

CROSSREFS

Sequence in context: A245570 A243925 A030727 * A269973 A128316 A065836

Adjacent sequences:  A278561 A278562 A278563 * A278565 A278566 A278567

KEYWORD

nonn,tabf

AUTHOR

N. J. A. Sloane, Nov 25 2016

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified June 17 19:57 EDT 2021. Contains 345085 sequences. (Running on oeis4.)