cp's OEIS Frontend

A252937 Number of nX7 nonnegative integer arrays with upper left 0 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 A252937 #6 Jul 23 2025 13:46:50
%S A252937 42,329,3016,30818,320270,2952734,21312696,113154831,440052087,
%T A252937 1302939451,3104860285,6297578921,11347942213,18725672417,28900783485,
%U A252937 42343299609,59523244981,80910643793,106975520237,138187898505
%N A252937 Number of nX7 nonnegative integer arrays with upper left 0 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 A252937 Column 7 of A252938
%H A252937 R. H. Hardin, <a href="/A252937/b252937.txt">Table of n, a(n) for n = 1..210</a>
%F A252937 Empirical: a(n) = (235012096/3)*n^3 - 1891478912*n^2 + (46791365972/3)*n - 43861899175 for n>12
%e A252937 Some solutions for n=4
%e A252937 ..0..1..1..2..3..3..3....0..1..2..2..3..3..4....0..1..1..2..2..3..3
%e A252937 ..1..1..1..2..3..3..3....1..1..2..2..3..4..4....1..1..1..2..2..3..3
%e A252937 ..1..2..2..2..3..3..3....1..1..2..2..3..4..4....1..1..2..2..3..3..3
%e A252937 ..2..2..2..3..3..3..4....1..2..2..2..3..4..5....2..2..2..2..3..4..4
%K A252937 nonn
%O A252937 1,1
%A A252937 _R. H. Hardin_, Dec 24 2014