A251976 Number of (n+2)X(1+2) 0..3 arrays with every 3X3 subblock row and column sum not 0 1 2 7 8 or 9 and every diagonal and antidiagonal sum 0 1 2 7 8 or 9

2930, 9822, 41682, 138390, 463054, 1762248, 6881308, 25756230, 95113860, 357237462, 1353522690, 5103212182, 19169232472, 72126802532, 271890916970, 1024595001512, 3858293820866, 14530015218650, 54736138173554

Offset

1,1

Comments

Column 1 of A251983

Links

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

Formula

Empirical: a(n) = 5*a(n-1) -3*a(n-2) -9*a(n-3) +41*a(n-4) -126*a(n-5) -40*a(n-6) +310*a(n-7) -7*a(n-8) +89*a(n-9) -70*a(n-10) -233*a(n-11) -393*a(n-12) +380*a(n-13) -164*a(n-14) -238*a(n-15) +36*a(n-16) +377*a(n-17) -61*a(n-18) +143*a(n-19) -46*a(n-20) -117*a(n-21) +153*a(n-22) +22*a(n-23) +93*a(n-24) -158*a(n-25) +114*a(n-26) +54*a(n-27) -68*a(n-28) +6*a(n-29) -16*a(n-30) +8*a(n-31) for n>34

Example

Some solutions for n=4
..2..0..3....0..2..2....0..3..0....0..3..0....0..3..1....0..2..1....0..3..0
..1..2..0....3..0..1....2..0..3....2..0..3....3..0..3....3..1..2....1..0..2
..2..1..3....0..3..2....1..3..1....1..2..0....1..2..0....0..3..1....2..3..1
..0..3..0....3..0..2....3..0..2....2..1..3....2..1..3....3..0..3....3..0..3
..2..0..2....0..3..0....1..3..1....0..3..0....1..3..0....1..3..1....0..3..0
..2..1..2....2..1..2....2..0..1....1..0..3....1..0..3....2..1..1....2..1..1

Crossrefs

Sequence in context: A276671 A251233 A251983 * A251975 A252198 A345570

Adjacent sequences: A251973 A251974 A251975 * A251977 A251978 A251979

Keyword

nonn

Author

R. H. Hardin, Dec 12 2014

Status

approved