A252440 Number of (7+2)X(n+2) 0..3 arrays with every 3X3 subblock row and diagonal sum equal to 0 2 4 6 or 7 and every 3X3 column and antidiagonal sum not equal to 0 2 4 6 or 7

2617, 13139, 59977, 139425, 920196, 4567070, 10924203, 71981082, 352414156, 842846501, 5554644436, 27198728509, 65131340122, 429210735737, 2099550371460, 5032430325465, 33168797168498, 162104514456916, 388927025159798

Offset

1,1

Comments

Row 7 of A252433

Links

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

Formula

Empirical: a(n) = 155*a(n-3) -5730*a(n-6) -42198*a(n-9) +1622879*a(n-12) +2030179*a(n-15) -187657035*a(n-18) +329658691*a(n-21) +10540844124*a(n-24) -43470613344*a(n-27) -231395084395*a(n-30) +1705391090763*a(n-33) -1594780828281*a(n-36) -8202243837085*a(n-39) +13649139340934*a(n-42) +11408920742626*a(n-45) -29209549804863*a(n-48) -304063398727*a(n-51) +24481787927247*a(n-54) -9525504172387*a(n-57) -6487954567720*a(n-60) +5786348853028*a(n-63) -1143496074997*a(n-66) -870646129079*a(n-69) +657803408582*a(n-72) -2585391262*a(n-75) -95561243336*a(n-78) +6093576096*a(n-81) +5181361248*a(n-84) -76463712*a(n-87) -25142400*a(n-90) for n>97

Example

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

Crossrefs

Sequence in context: A257427 A257420 A254236 * A066871 A180650 A245008

Adjacent sequences: A252437 A252438 A252439 * A252441 A252442 A252443

Keyword

nonn

Author

R. H. Hardin, Dec 17 2014

Status

approved