One-third of the number of n X n nonnegative integer arrays with every 3 X 3 subblock summing to 1.

A145052

One-third of the number of n X n nonnegative integer arrays with every 3 X 3 subblock summing to 1.

Terms

    a(0) =3a(1) =7a(2) =11a(3) =15a(4) =27a(5) =39a(6) =51a(7) =87a(8) =123a(9) =159a(10) =267a(11) =375a(12) =483a(13) =807a(14) =1131a(15) =1455a(16) =2427a(17) =3399a(18) =4371a(19) =7287a(20) =10203a(21) =13119a(22) =21867a(23) =30615

External references