cp's OEIS Frontend

A212044 T(n,k)=Number of lower triangular n X n arrays colored with integers 0 upwards introduced in row major order, with no element equal to any element within a city block distance of two, and containing the value n(n+1)/2-k-1.

%I A212044 #7 Jun 02 2025 07:55:03
%S A212044 0,0,1,0,1,4,0,0,5,19,0,0,5,119,58,0,0,5,319,1310,136,0,0,5,447,14949,
%T A212044 7849,271,0,0,0,463,94131,253072,32696,484,0,0,0,463,339764,5054845,
%U A212044 2326567,107400,799,0,0,0,463,728291,65635205,109065807,14516200,298404
%N A212044 T(n,k)=Number of lower triangular n X n arrays colored with integers 0 upwards introduced in row major order, with no element equal to any element within a city block distance of two, and containing the value n(n+1)/2-k-1.
%C A212044 Table starts
%C A212044 ...0......0........0..........0...........0...........0..........0...........0
%C A212044 ...1......1........0..........0...........0...........0..........0...........0
%C A212044 ...4......5........5..........5...........5...........0..........0...........0
%C A212044 ..19....119......319........447.........463.........463........463.........463
%C A212044 ..58...1310....14949......94131......339764......728291....1010440.....1087168
%C A212044 .136...7849...253072....5054845....65635205...566694913.3281785526.12771345347
%C A212044 .271..32696..2326567..109065807..3564578765.83865812963
%C A212044 .484.107400.14516200.1339229741.89579748909
%H A212044 R. H. Hardin, <a href="/A212044/b212044.txt">Table of n, a(n) for n = 1..84</a>
%e A212044 Some solutions for n=4 k=4
%e A212044 ..0........0........0........0........0........0........0........0
%e A212044 ..1.2......1.2......1.2......1.2......1.2......1.2......1.2......1.2
%e A212044 ..3.4.1....3.4.1....3.4.5....3.0.4....3.0.4....3.4.1....3.4.0....3.4.5
%K A212044 nonn,tabl
%O A212044 1,6
%A A212044 _R. H. Hardin_ Apr 28 2012