cp's OEIS Frontend

A195280 Number of lower triangles of a 4X4 integer array with each element differing from all of its vertical and horizontal neighbors by n or less and triangles differing by a constant counted only once.

%I A195280 #7 Jul 22 2025 12:43:47
%S A195280 6939,626525,12608631,119743353,724789395,3249312469,11755976175,
%T A195280 36215968241,98454861067,242177297229,548894457959,1162058315625,
%U A195280 2322243189891,4416808121541,8048123047903,14125147709409,23983914638075
%N A195280 Number of lower triangles of a 4X4 integer array with each element differing from all of its vertical and horizontal neighbors by n or less and triangles differing by a constant counted only once.
%C A195280 Row 4 of A195278
%H A195280 R. H. Hardin, <a href="/A195280/b195280.txt">Table of n, a(n) for n = 1..169</a>
%F A195280 Empirical: a(n) = (49024/315)*n^9 + (24512/35)*n^8 + (457792/315)*n^7 + (81824/45)*n^6 + (67912/45)*n^5 + (38756/45)*n^4 + (11832/35)*n^3 + (27752/315)*n^2 + (1454/105)*n + 1
%e A195280 Some solutions for n=5
%e A195280 ...0............0............0............0............0............0
%e A195280 ..-1.-2.........1..1.........5..3.........3..1........-1.-3.........3..4
%e A195280 ..-6.-5.-6.....-2..2.-1......5..3..1......7..4..2......1..1.-2......0..4..1
%e A195280 ..-2.-1.-1..1...3..6..2..0...1.-2..3..1...5..3.-2.-1..-2..2..1..1..-5..0..2..1
%K A195280 nonn
%O A195280 1,1
%A A195280 _R. H. Hardin_ Sep 14 2011