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A252416
Number of (n+2)X(1+2) 0..3 arrays with every 3X3 subblock row and column sum not equal to 0 2 5 6 or 7 and every 3X3 diagonal and antidiagonal sum equal to 0 2 5 6 or 7
1
830, 1006, 1099, 1536, 2380, 3719, 5725, 9410, 15913, 24959, 41482, 71673, 113483, 190458, 331355, 528273, 890510, 1550563, 2484529, 4198986, 7302055, 11748241, 19885680, 34513509, 55726873, 94410220, 163496363, 264847361, 448910350
OFFSET
1,1
COMMENTS
Column 1 of A252423
LINKS
FORMULA
Empirical: a(n) = -a(n-1) -a(n-2) +15*a(n-3) +15*a(n-4) +15*a(n-5) -87*a(n-6) -86*a(n-7) -83*a(n-8) +256*a(n-9) +243*a(n-10) +212*a(n-11) -455*a(n-12) -388*a(n-13) -273*a(n-14) +622*a(n-15) +437*a(n-16) +231*a(n-17) -769*a(n-18) -437*a(n-19) -200*a(n-20) +840*a(n-21) +360*a(n-22) +93*a(n-23) -826*a(n-24) -210*a(n-25) +81*a(n-26) +707*a(n-27) +74*a(n-28) -162*a(n-29) -496*a(n-30) +3*a(n-31) +162*a(n-32) +314*a(n-33) -27*a(n-34) -134*a(n-35) -166*a(n-36) +35*a(n-37) +92*a(n-38) +54*a(n-39) -22*a(n-40) -39*a(n-41) -8*a(n-42) +4*a(n-43) +6*a(n-44) for n>49
EXAMPLE
Some solutions for n=4
..0..1..0....3..2..3....1..2..0....0..3..1....1..0..0....1..2..1....1..1..2
..1..2..1....0..3..0....2..1..1....2..0..1....2..1..1....3..1..0....3..0..1
..0..1..3....0..3..0....1..0..3....1..0..2....1..3..0....0..1..3....0..0..1
..0..1..0....3..2..3....1..0..0....1..3..0....1..0..0....1..2..1....1..1..2
..1..2..1....0..3..0....2..1..1....2..1..1....2..1..1....0..1..0....0..0..1
..0..1..0....1..3..0....1..0..3....1..0..3....1..0..3....3..1..0....0..2..1
CROSSREFS
Sequence in context: A366704 A252415 A252423 * A125519 A351666 A045070
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 17 2014
STATUS
approved