A252197 Number of (n+2)X(4+2) 0..3 arrays with every 3X3 subblock row, column, diagonal and antidiagonal sum not equal to 0 3 5 6 or 7

1642, 1313, 5177, 21928, 92287, 391996, 1669356, 7114929, 30309104, 129016093, 549319099, 2339547062, 9963141907, 42425232312, 180661430088, 769335984235, 3276146397900, 13951092432241, 59409215104055, 252988054381960

Offset

1,1

Comments

Column 4 of A252201

Links

R. H. Hardin, Table of n, a(n) for n = 1..210

Formula

Empirical: a(n) = 2*a(n-1) +5*a(n-2) +14*a(n-3) +34*a(n-4) -16*a(n-5) -79*a(n-6) -150*a(n-7) -94*a(n-8) +581*a(n-9) +457*a(n-10) -913*a(n-11) -631*a(n-12) +692*a(n-13) +433*a(n-14) -236*a(n-15) -116*a(n-16) +72*a(n-17) -57*a(n-18) -32*a(n-19) +38*a(n-20) -15*a(n-21) +5*a(n-22) +11*a(n-23) -4*a(n-24) for n>28

Example

Some solutions for n=4
..3..3..3..2..3..3....3..2..3..3..3..3....3..3..3..3..2..3....2..3..3..3..3..2
..2..3..3..3..3..3....3..3..3..3..3..3....3..2..3..3..3..3....3..3..2..3..3..3
..3..3..3..3..3..3....3..3..3..3..3..3....3..3..3..3..3..2....3..3..3..3..3..3
..3..3..3..3..3..3....3..3..3..3..3..3....2..3..3..3..3..3....3..2..3..3..3..2
..3..3..3..3..2..3....3..3..3..3..3..2....3..3..3..3..3..3....3..3..3..3..3..3
..3..2..3..3..3..3....3..2..3..3..3..3....3..2..3..3..3..3....3..3..2..3..3..3

Crossrefs

Sequence in context: A035866 A015340 A272127 * A135016 A238066 A349178

Adjacent sequences: A252194 A252195 A252196 * A252198 A252199 A252200

Keyword

nonn

Author

R. H. Hardin, Dec 15 2014

Status

approved