cp's OEIS Frontend

A253003 Number of nX7 nonnegative integer arrays with upper left 0 and lower right its king-move distance away minus 3 and every value within 3 of its king move distance from the upper left and every value increasing by 0 or 1 with every step right, diagonally se or down.

%I A253003 #6 Jul 23 2025 13:51:07
%S A253003 20,140,1028,7235,39758,122833,122833,4915726,59154789,329035981,
%T A253003 1124010769,2853903059,5973571711,10950733467,18255251895,28357151187,
%U A253003 41726455535,58833189131,80147376167,106139040835,137278207327
%N A253003 Number of nX7 nonnegative integer arrays with upper left 0 and lower right its king-move distance away minus 3 and every value within 3 of its king move distance from the upper left and every value increasing by 0 or 1 with every step right, diagonally se or down.
%C A253003 Column 7 of A253004
%H A253003 R. H. Hardin, <a href="/A253003/b253003.txt">Table of n, a(n) for n = 1..210</a>
%F A253003 Empirical: a(n) = (235012096/3)*n^3 - 2126491008*n^2 + (58625640404/3)*n - 60801081325 for n>12
%e A253003 Some solutions for n=6
%e A253003 ..0..1..1..1..1..2..3....0..0..1..1..1..2..3....0..1..1..1..2..3..3
%e A253003 ..1..1..1..1..2..2..3....0..0..1..1..2..2..3....0..1..2..2..2..3..3
%e A253003 ..1..1..1..1..2..2..3....0..1..1..1..2..2..3....1..1..2..2..2..3..3
%e A253003 ..1..1..2..2..2..3..3....0..1..1..2..2..3..3....1..1..2..2..3..3..3
%e A253003 ..1..2..2..2..3..3..3....1..1..1..2..3..3..3....2..2..2..3..3..3..3
%e A253003 ..2..2..2..3..3..3..3....2..2..2..2..3..3..3....2..2..3..3..3..3..3
%K A253003 nonn
%O A253003 1,1
%A A253003 _R. H. Hardin_, Dec 25 2014