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.

A220028 Number of n X n arrays of the minimum value of corresponding elements and their horizontal or diagonal neighbors in a random, but sorted with lexicographically nondecreasing rows and nonincreasing columns, 0..1 n X n array.

This page as a plain text file.
%I A220028 #7 Jul 23 2025 00:50:47
%S A220028 2,4,10,34,111,358,1165,3789,12375,40583,133632,441773
%N A220028 Number of n X n arrays of the minimum value of corresponding elements and their horizontal or diagonal neighbors in a random, but sorted with lexicographically nondecreasing rows and nonincreasing columns, 0..1 n X n array.
%C A220028 Diagonal of A220032
%e A220028 Some solutions for n=3
%e A220028 ..0..0..0....1..0..0....0..0..0....0..0..0....0..0..0....0..0..0....1..0..0
%e A220028 ..0..0..0....1..0..0....0..0..0....1..0..0....0..0..0....1..0..0....1..1..1
%e A220028 ..1..0..0....1..1..1....0..0..0....1..1..1....1..1..0....1..0..0....1..1..1
%K A220028 nonn
%O A220028 1,1
%A A220028 _R. H. Hardin_ Dec 03 2012