A185744 Number of (n+1)X4 binary arrays with every 2X2 subblock trace equal to some horizontal or vertical neighbor 2X2 subblock trace

40, 544, 4056, 33768, 273928, 2237680, 18242392, 148782184, 1213377952, 9895860408, 80705698992, 658196978784, 5367941569504, 43778383255816, 357035645118432, 2911812758671528, 23747359117977160, 193672159175543352

Offset

1,1

Comments

Column 3 of A185750

Links

R. H. Hardin, Table of n, a(n) for n = 1..200

Formula

Empirical: a(n)=9*a(n-1)-17*a(n-2)+73*a(n-3)+92*a(n-4)-240*a(n-5)+1138*a(n-6)-856*a(n-7)-4412*a(n-8)+5722*a(n-9)+7036*a(n-10)-23333*a(n-11)-7776*a(n-12)+19505*a(n-13)+27120*a(n-14)+27301*a(n-15)-16807*a(n-16)-83683*a(n-17)+14978*a(n-18)+28073*a(n-19)+37181*a(n-20)-34392*a(n-21)+3645*a(n-22)-1339*a(n-23)-5386*a(n-24)-26621*a(n-25)+37448*a(n-26)-1164*a(n-27)+4386*a(n-28)-4788*a(n-29)-5243*a(n-30)+3211*a(n-31)-193*a(n-32)+52*a(n-33)+344*a(n-34)+16*a(n-35)-128*a(n-36)

Example

Some solutions for 3X4
..1..1..1..0....1..1..0..0....1..1..1..1....1..1..0..1....1..0..0..0
..1..0..1..1....1..1..1..1....1..1..0..0....1..0..0..1....1..1..1..1
..1..0..1..0....0..1..1..0....1..1..0..1....0..0..1..1....0..1..1..0

Crossrefs

Sequence in context: A247409 A107419 A159946 * A269497 A097823 A263953

Adjacent sequences: A185741 A185742 A185743 * A185745 A185746 A185747

Keyword

nonn

Author

R. H. Hardin Feb 01 2011

Status

approved