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.

A187698 Number of (n+1)X(n+1) 0..3 arrays with each 2X2 subblock determinant nonzero and the array of 2X2 subblock determinants symmetric under horizontal and vertical reflection.

Table of values

n a(n)
1 192
2 74
3 87258
4 22738
5 1089964504

List of values

[192, 74, 87258, 22738, 1089964504]

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

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