A282881 Number of nX4 0..1 arrays with no 1 equal to more than one of its horizontal, vertical and antidiagonal neighbors, with the exception of exactly one element.
2, 32, 430, 3762, 34314, 286920, 2342046, 18668994, 146171090, 1129426388, 8631205392, 65377140772, 491525631332, 3672205687546, 27287152439396, 201813637267634, 1486474449573152, 10909072654743782, 79802389614658676
Offset: 1
Keywords
Examples
Some solutions for n=4 ..1..1..0..0. .1..0..0..1. .0..1..0..0. .0..0..0..0. .0..1..1..0 ..0..1..0..1. .1..1..0..0. .1..0..0..0. .1..0..0..0. .1..0..0..0 ..0..0..0..1. .0..0..1..0. .0..0..1..1. .0..1..1..0. .0..1..0..0 ..0..1..0..0. .1..0..0..1. .0..0..0..1. .0..0..1..0. .1..0..1..1
Links
- R. H. Hardin, Table of n, a(n) for n = 1..210
Crossrefs
Cf. A282885.
Formula
Empirical: a(n) = 2*a(n-1) +47*a(n-2) +124*a(n-3) -408*a(n-4) -3902*a(n-5) -15430*a(n-6) -42962*a(n-7) -94378*a(n-8) -169172*a(n-9) -254731*a(n-10) -324792*a(n-11) -346186*a(n-12) -306142*a(n-13) -226049*a(n-14) -101410*a(n-15) -32004*a(n-16) +9038*a(n-17) +56744*a(n-18) +18514*a(n-19) -78727*a(n-20) +278126*a(n-21) -491637*a(n-22) +664706*a(n-23) -600043*a(n-24) +363134*a(n-25) -86242*a(n-26) -73590*a(n-27) +88574*a(n-28) -49032*a(n-29) +20328*a(n-30) -6196*a(n-31) -2591*a(n-32) +4334*a(n-33) -1998*a(n-34) +278*a(n-35) +31*a(n-36) -40*a(n-37) +63*a(n-38) -34*a(n-39) +2*a(n-40) +4*a(n-41) -a(n-42)
Comments