1/6 the number of (n+2)X4 0..2 arrays with each 3X3 subblock containing one of one value, four of another, and four of the last.
A184470
1/6 the number of (n+2)X4 0..2 arrays with each 3X3 subblock containing one of one value, four of another, and four of the last.
Terms
- a(0) =1095a(1) =2755a(2) =7085a(3) =19119a(4) =62213a(5) =200215a(6) =645837a(7) =2386807a(8) =8440325a(9) =29121087a(10) =112850957a(11) =413112487a(12) =1461095205a(13) =5765335615a(14) =21394180445a(15) =76423033479a(16) =303819408773
External references
- oeis: A184470