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 A219686 #6 Jul 23 2025 00:36:29 %S A219686 3,3,3,6,4,6,10,8,9,10,15,14,31,19,15,21,22,87,99,35,21,28,32,208,427, %T A219686 269,60,28,36,44,452,1531,1688,655,98,36,45,58,922,5031,8964,5726, %U A219686 1506,154,45,55,74,1799,15763,44736,44816,18486,3356,234,55,66,92,3394,47784 %N A219686 T(n,k)=Number of nXk arrays of the minimum value of corresponding elements and their horizontal, vertical or antidiagonal neighbors in a random, but sorted with lexicographically nondecreasing rows and nonincreasing columns, 0..2 nXk array. %C A219686 Table starts %C A219686 ..3...3.....6......10........15.........21.........28..........36.........45 %C A219686 ..3...4.....8......14........22.........32.........44..........58.........74 %C A219686 ..6...9....31......87.......208........452........922........1799.......3394 %C A219686 .10..19....99.....427......1531.......5031......15763.......47784.....140586 %C A219686 .15..35...269....1688......8964......44736.....219216.....1062133....5046678 %C A219686 .21..60...655....5726.....44816.....344926....2709320....21474269..167685059 %C A219686 .28..98..1506...18486....220182....2706117...35011623...461414270.5979059010 %C A219686 .36.154..3356...59458...1116208...22404783..479633094.10451333258 %C A219686 .45.234..7278..189516...5697556..187497531.6609458081 %C A219686 .55.345.15335..589078..28354294.1518906665 %C A219686 .66.495.31362.1771979.135630422 %C A219686 .78.693.62286.5155016 %H A219686 R. H. Hardin, <a href="/A219686/b219686.txt">Table of n, a(n) for n = 1..127</a> %e A219686 Some solutions for n=3 k=4 %e A219686 ..1..1..1..1....0..0..0..0....1..1..0..0....1..1..0..0....1..1..1..0 %e A219686 ..1..1..1..1....0..0..0..0....1..1..0..0....1..0..0..0....1..1..0..0 %e A219686 ..2..1..1..1....1..1..0..0....2..2..0..0....2..0..0..0....2..2..0..0 %Y A219686 Column 1 and row 1 are A000217 for n>1 %Y A219686 Row 2 is A003682 for n>1 %K A219686 nonn,tabl %O A219686 1,1 %A A219686 _R. H. Hardin_ Nov 25 2012