A252598 Number of (n+2)X(1+2) 0..2 arrays with every 3X3 subblock row, column, diagonal and antidiagonal sum not equal to 1 2 or 5

303, 567, 1218, 2792, 6709, 16123, 39372, 97138, 239542, 594231, 1478086, 3673617, 9149192, 22806844, 56828222, 141709958, 353502123, 881648042, 2199536221, 5488280380, 13693103367, 34168135962, 85265526852, 212769328749

Offset

1,1

Comments

Column 1 of A252605

Links

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

Formula

Empirical: a(n) = 4*a(n-1) -6*a(n-2) +31*a(n-3) -92*a(n-4) +124*a(n-5) -375*a(n-6) +811*a(n-7) -979*a(n-8) +2278*a(n-9) -3380*a(n-10) +3698*a(n-11) -7324*a(n-12) +6163*a(n-13) -6909*a(n-14) +11385*a(n-15) -602*a(n-16) +6670*a(n-17) -3170*a(n-18) -12304*a(n-19) -6355*a(n-20) -14914*a(n-21) +8655*a(n-22) +7225*a(n-23) +20083*a(n-24) +9981*a(n-25) -963*a(n-26) -7637*a(n-27) -9987*a(n-28) -1830*a(n-29) +1511*a(n-30) +3257*a(n-31) +530*a(n-32) -1400*a(n-33) -2384*a(n-34) -1532*a(n-35) -732*a(n-36) +60*a(n-37) +226*a(n-38) +120*a(n-39) +80*a(n-40) -20*a(n-41) +12*a(n-42) -8*a(n-43) for n>47

Example

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

Crossrefs

Sequence in context: A255144 A098241 A252605 * A252597 A237093 A236813

Adjacent sequences: A252595 A252596 A252597 * A252599 A252600 A252601

Keyword

nonn

Author

R. H. Hardin, Dec 19 2014

Status

approved