Number of (n+1) X (2+1) 0..3 arrays with every 2 X 2 subblock summing to 6 and no 2 X 2 subblock having exactly two nonzero entries.

A251230

Number of (n+1) X (2+1) 0..3 arrays with every 2 X 2 subblock summing to 6 and no 2 X 2 subblock having exactly two nonzero entries.

Terms

    a(0) =110a(1) =270a(2) =694a(3) =1870a(4) =5194a(5) =14786a(6) =42850a(7) =125934a(8) =374166a(9) =1121566a(10) =3386570a(11) =10289714a(12) =31434338a(13) =96493518a(14) =297491174a(15) =920787166a(16) =2860264522a(17) =8914266818a(18) =27866446818a(19) =87355159854a(20) =274542478518a(21) =864878298334

External references