A212041 - OEIS

A212041

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)/2-4

%I #4 Dec 18 2015 18:18:10

%S 0,0,5,319,14949,253072,2326567,14516200,69305994,271885024,917364452,

%T 2746402607,7459357270

%N 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)/2-4

%C Column 3 of A212044

%e Some solutions for n=4

%e ..0........0........0........0........0........0........0........0

%e ..1.2......1.2......1.2......1.2......1.2......1.2......1.2......1.2

%e ..3.0.4....3.4.5....3.4.1....3.4.0....3.0.4....3.4.5....3.4.5....3.0.4

%e ..5.6.2.5..0.6.7.3..5.0.6.4..5.6.7.2..5.6.3.0..6.0.1.3..0.6.7.1..2.1.5.6

%K nonn

%O 1,3

%A _R. H. Hardin_ Apr 28 2012