Number of (n+2)X(1+2) 0..3 arrays with every 3X3 subblock row and column sum not 3 or 6 and every diagonal and antidiagonal sum 3 or 6.
A251822
Number of (n+2)X(1+2) 0..3 arrays with every 3X3 subblock row and column sum not 3 or 6 and every diagonal and antidiagonal sum 3 or 6.
Terms
- a(0) =1890a(1) =3930a(2) =9354a(3) =22266a(4) =61058a(5) =160322a(6) =413202a(7) =1139826a(8) =3118482a(9) =8319882a(10) =23584586a(11) =65465226a(12) =178084738a(13) =504244530a(14) =1412258994a(15) =3880043794a(16) =11020794162a(17) =30982240178a(18) =85749834586a(19) =243381206194a(20) =686186919786
External references
- oeis: A251822