cp's OEIS Frontend

A225013 Number of 6Xn 0..1 arrays with rows unimodal and columns nondecreasing.

%I A225013 #6 Jul 23 2025 05:20:28
%S A225013 7,49,252,1036,3612,11088,30738,78354,186142,416394,884236,1794196,
%T A225013 3497248,6577474,11980667,21201211,36548573,61520899,101320712,
%U A225013 163556776,259187048,403770544,619111172,935394436,1393938716,2050706932
%N A225013 Number of 6Xn 0..1 arrays with rows unimodal and columns nondecreasing.
%C A225013 Row 6 of A225010
%H A225013 R. H. Hardin, <a href="/A225013/b225013.txt">Table of n, a(n) for n = 1..210</a>
%F A225013 Empirical: a(n) = (1/479001600)*n^12 + (1/7257600)*n^11 + (187/43545600)*n^10 + (13/161280)*n^9 + (14671/14515200)*n^8 + (3043/345600)*n^7 + (2380201/43545600)*n^6 + (347911/1451520)*n^5 + (8129699/10886400)*n^4 + (923183/604800)*n^3 + (913741/415800)*n^2 + (49/40)*n + 1
%e A225013 Some solutions for n=3
%e A225013 ..0..0..0....0..0..0....0..0..0....0..0..0....0..0..0....0..1..0....1..1..0
%e A225013 ..0..1..0....0..0..0....0..1..0....0..0..0....0..0..0....0..1..1....1..1..0
%e A225013 ..0..1..0....1..0..0....0..1..1....0..1..0....1..0..0....0..1..1....1..1..0
%e A225013 ..0..1..0....1..1..0....0..1..1....0..1..0....1..0..0....0..1..1....1..1..0
%e A225013 ..1..1..0....1..1..0....1..1..1....0..1..0....1..0..0....0..1..1....1..1..1
%e A225013 ..1..1..1....1..1..0....1..1..1....0..1..0....1..0..0....1..1..1....1..1..1
%K A225013 nonn
%O A225013 1,1
%A A225013 _R. H. Hardin_ Apr 23 2013