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 A224170 #9 Mar 18 2025 20:55:12 %S A224170 296,14751,242114,2335459,16625026,95808564,468021427,1994287334, %T A224170 7568051210,25994968917,81880904262,239073335825,652853600502, %U A224170 1679943141302,4099447427041,9538065127010,21257876699694,45567034926263,94269674457770,188804401330651,367061634874676 %N A224170 Number of n X 5 0..3 arrays with rows, diagonals and antidiagonals unimodal and columns nondecreasing. %H A224170 R. H. Hardin, <a href="/A224170/b224170.txt">Table of n, a(n) for n = 1..210</a> %F A224170 Empirical: a(n) = (769/444787200)*n^15 + (348923/10897286400)*n^14 + (103091/194594400)*n^13 + (52907/9580032)*n^12 + (943843/19958400)*n^11 + (2062183/7257600)*n^10 + (18840953/10886400)*n^9 + (179917349/30481920)*n^8 + (117380839/4354560)*n^7 + (1362686849/21772800)*n^6 + (9998925647/39916800)*n^5 - (85242803/147840)*n^4 + (54417504217/43243200)*n^3 - (64383420173/12612600)*n^2 + (221650083/10010)*n - 34678 for n>6. %e A224170 Some solutions for n=3: %e A224170 ..0..0..0..1..1....0..0..0..2..1....0..0..0..0..0....0..0..0..1..0 %e A224170 ..0..0..3..3..3....0..2..3..2..2....0..1..1..2..0....1..3..1..1..0 %e A224170 ..0..1..3..3..3....0..3..3..3..2....0..1..2..2..2....1..3..2..2..2 %Y A224170 Column 5 of A224173. %K A224170 nonn %O A224170 1,1 %A A224170 _R. H. Hardin_, Mar 31 2013 %E A224170 Name corrected by _Andrew Howroyd_, Mar 18 2025