cp's OEIS Frontend

A194495 Number of ways to arrange 5 nonattacking queens on the lower triangle of an n X n board.

%I A194495 #8 Jul 22 2025 12:33:31
%S A194495 0,0,0,0,0,0,4,114,1384,9890,50662,205512,698688,2074530,5525902,
%T A194495 13476246,30522678,64968996,131070600,252492296,467017054,833501728,
%U A194495 1440839952,2420878990,3964168632,6342428908,9934738024,15264432954
%N A194495 Number of ways to arrange 5 nonattacking queens on the lower triangle of an n X n board.
%C A194495 Column 5 of A194498
%H A194495 R. H. Hardin, <a href="/A194495/b194495.txt">Table of n, a(n) for n = 1..49</a>
%e A194495 All solutions for 7X7
%e A194495 ..0..............0..............0..............0
%e A194495 ..0.0............0.0............0.0............0.0
%e A194495 ..1.0.0..........0.1.0..........1.0.0..........0.0.1
%e A194495 ..0.0.0.1........0.0.0.1........0.0.1.0........1.0.0.0
%e A194495 ..0.1.0.0.0......1.0.0.0.0......0.0.0.0.1......0.0.0.1.0
%e A194495 ..0.0.0.0.1.0....0.0.1.0.0.0....0.1.0.0.0.0....0.1.0.0.0.0
%e A194495 ..0.0.1.0.0.0.0..0.0.0.0.1.0.0..0.0.0.1.0.0.0..0.0.0.0.1.0.0
%K A194495 nonn
%O A194495 1,7
%A A194495 _R. H. Hardin_ Aug 26 2011