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A252599
Number of (n+2)X(2+2) 0..2 arrays with every 3X3 subblock row, column, diagonal and antidiagonal sum not equal to 1 2 or 5
1
567, 1151, 2784, 6978, 18454, 49782, 136336, 380466, 1070438, 3029761, 8627013, 24630825, 70475042, 202058195, 579821752, 1665118858, 4785253832, 13755703417, 39553064198, 113760165084, 327218002791, 941299811884, 2708082174203
OFFSET
1,1
COMMENTS
Column 2 of A252605
LINKS
FORMULA
Empirical: a(n) = 5*a(n-1) -5*a(n-2) +34*a(n-3) -174*a(n-4) +140*a(n-5) -424*a(n-6) +2467*a(n-7) -1397*a(n-8) +2172*a(n-9) -18422*a(n-10) +4858*a(n-11) -1464*a(n-12) +77576*a(n-13) +9979*a(n-14) -22996*a(n-15) -174917*a(n-16) -115360*a(n-17) +30816*a(n-18) +113842*a(n-19) +235356*a(n-20) +230348*a(n-21) +448600*a(n-22) +168906*a(n-23) -574333*a(n-24) -1229468*a(n-25) -1066813*a(n-26) -121034*a(n-27) +670736*a(n-28) +869462*a(n-29) +1099158*a(n-30) +1311747*a(n-31) +750304*a(n-32) -605799*a(n-33) -1666321*a(n-34) -1369984*a(n-35) -283531*a(n-36) +457266*a(n-37) +509503*a(n-38) +374550*a(n-39) +333752*a(n-40) +106961*a(n-41) -301231*a(n-42) -478660*a(n-43) -278163*a(n-44) +56909*a(n-45) +206210*a(n-46) +167397*a(n-47) +109808*a(n-48) +72846*a(n-49) +8411*a(n-50) -61728*a(n-51) -79089*a(n-52) -30078*a(n-53) +19861*a(n-54) +29055*a(n-55) +14462*a(n-56) +3006*a(n-57) -313*a(n-58) -3155*a(n-59) -6796*a(n-60) -6304*a(n-61) -1997*a(n-62) +1116*a(n-63) +1496*a(n-64) +698*a(n-65) +144*a(n-66) for n>69
EXAMPLE
Some solutions for n=4
..2..1..1..2....2..2..2..2....2..2..0..2....2..2..0..2....2..2..2..2
..0..1..2..0....2..2..2..2....2..2..2..2....2..0..1..2....2..2..2..2
..1..2..0..1....2..2..2..0....2..2..2..2....0..1..2..0....2..2..2..0
..2..0..1..2....2..0..2..2....0..0..0..0....1..2..0..2....2..2..2..2
..0..1..2..0....2..2..2..2....1..2..1..1....2..0..1..2....2..2..2..2
..2..2..0..2....2..2..2..2....2..2..2..2....0..1..2..0....0..0..0..0
CROSSREFS
Sequence in context: A189352 A005953 A051372 * A023099 A209954 A233057
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 19 2014
STATUS
approved