cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

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A051759 Consider the problem of placing A051756(n) queens on an n X n board so that each queen attacks precisely 3 others. Sequence gives number of solutions up to square symmetry.

Original entry on oeis.org

1, 2, 4, 31, 307, 2, 9, 755
Offset: 2

Views

Author

Robert Trent (trentrd(AT)hotmail.com), Aug 23 2000

Keywords

Comments

A051569 (taken from the Martin Gardner references) is another version of this sequence. - N. J. A. Sloane, May 22 2014

References

  • M. Gardner, The Last Recreations, Springer, 1997, p. 282.
  • M. Gardner, The Colossal Book of Mathematics, 2001, p. 209.

Links

Crossrefs

Cf. A051754-A051758, A051567-A051571, A019654.

Extensions

a(8)-a(9) from Sean A. Irvine, Oct 01 2021

A051569 Consider the problem of placing N = A051756(n) queens on an n X n board so that each queen attacks precisely 3 others; a(n) gives the number of inequivalent solutions.

Original entry on oeis.org

1, 2, 4, 31, 304, 2, 9, 755, 39302
Offset: 2

Views

Author

N. J. A. Sloane

Keywords

References

  • M. Gardner, The Last Recreations, Springer, 1997, p. 282.
  • M. Gardner, The Colossal Book of Mathematics, 2001, p. 209.

Crossrefs

Cf. A051567-A051571, A051754-A051759, A019654.

Extensions

I am not certain this description is correct, nor how rigorous the results are. Probably this is an incorrect version of A051759.
Showing 1-2 of 2 results.

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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