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

%I #4 Apr 23 2013 21:56:06

%S 7,49,252,1036,3612,11088,30738,78354,186142,416394,884236,1794196,

%T 3497248,6577474,11980667,21201211,36548573,61520899,101320712,

%U 163556776,259187048,403770544,619111172,935394436,1393938716,2050706932

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

%C Row 6 of A225010

%H R. H. Hardin, <a href="/A225013/b225013.txt">Table of n, a(n) for n = 1..210</a>

%F 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 Some solutions for n=3

%e ..0..0..0....0..0..0....0..0..0....0..0..0....0..0..0....0..1..0....1..1..0

%e ..0..1..0....0..0..0....0..1..0....0..0..0....0..0..0....0..1..1....1..1..0

%e ..0..1..0....1..0..0....0..1..1....0..1..0....1..0..0....0..1..1....1..1..0

%e ..0..1..0....1..1..0....0..1..1....0..1..0....1..0..0....0..1..1....1..1..0

%e ..1..1..0....1..1..0....1..1..1....0..1..0....1..0..0....0..1..1....1..1..1

%e ..1..1..1....1..1..0....1..1..1....0..1..0....1..0..0....1..1..1....1..1..1

%K nonn

%O 1,1

%A _R. H. Hardin_ Apr 23 2013

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Last modified April 23 02:53 EDT 2024. Contains 371906 sequences. (Running on oeis4.)