Number of (n+2) X 4 0..3 arrays with every 3 X 3 subblock commuting with each horizontal and vertical neighbor 3 X 3 subblock.

A186874

Number of (n+2) X 4 0..3 arrays with every 3 X 3 subblock commuting with each horizontal and vertical neighbor 3 X 3 subblock.

Terms

    a(0) =2428a(1) =421a(2) =1201a(3) =6829a(4) =14221a(5) =18517a(6) =21661a(7) =25381a(8) =34645a(9) =64384a(10) =118027a(11) =201190a(12) =355210a(13) =592102a(14) =945346a(15) =1600378a(16) =2664955a(17) =4328077a(18) =7358623a(19) =12328480a(20) =20153704a(21) =34046296a(22) =56950552a(23) =93410275a(24) =157163740a(25) =262861768a(26) =432701869a(27) =726100972

External references