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.
%I A218521 #6 Jul 22 2025 23:57:47 %S A218521 602,242438,100029148,38497164700,15254005086276,5977895789290552, %T A218521 2345237392530015812,920135128267216305816,361061212834288178529464, %U A218521 141687156380002483076174644,55601697647561060078651796422 %N A218521 Number of nX7 arrays of the minimum value of corresponding elements and their horizontal or antidiagonal neighbors in a random 0..3 nX7 array. %C A218521 Column 7 of A218522 %H A218521 R. H. Hardin, <a href="/A218521/b218521.txt">Table of n, a(n) for n = 1..53</a> %e A218521 Some solutions for n=3 %e A218521 ..0..0..0..0..0..3..3....0..0..0..0..1..0..0....0..0..0..0..0..0..1 %e A218521 ..0..0..0..0..1..2..2....0..0..0..1..2..0..0....0..0..0..0..1..0..0 %e A218521 ..0..0..0..2..3..1..1....0..1..3..2..1..0..1....0..0..2..3..1..0..3 %K A218521 nonn %O A218521 1,1 %A A218521 _R. H. Hardin_ Oct 31 2012