login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A252028
Number of (n+2)X(4+2) 0..2 arrays with every 3X3 subblock row, column, diagonal and antidiagonal sum not equal to 0 2 or 4
1
809, 1929, 7182, 29781, 126920, 541544, 2306234, 9836361, 42007667, 179412369, 766247783, 3273106717, 13982899118, 59736693957, 255202401835, 1090262794558, 4657798693225, 19899000968428, 85012294225985, 363188622741325
OFFSET
1,1
COMMENTS
Column 4 of A252032
LINKS
FORMULA
Empirical: a(n) = 5*a(n-1) -4*a(n-2) +14*a(n-3) -23*a(n-4) -91*a(n-5) -13*a(n-6) -118*a(n-7) +815*a(n-8) +1080*a(n-9) -692*a(n-10) -2103*a(n-11) -5420*a(n-12) +2379*a(n-13) +8473*a(n-14) +4179*a(n-15) +8147*a(n-16) -18588*a(n-17) -30186*a(n-18) +2771*a(n-19) +28308*a(n-20) +32734*a(n-21) +6559*a(n-22) -23299*a(n-23) -16727*a(n-24) -666*a(n-25) +7553*a(n-26) -5973*a(n-27) -14481*a(n-28) +7873*a(n-29) +34754*a(n-30) +25934*a(n-31) -15978*a(n-32) -45920*a(n-33) -43974*a(n-34) -14735*a(n-35) +6402*a(n-36) +15091*a(n-37) +14803*a(n-38) +11460*a(n-39) +9120*a(n-40) +5581*a(n-41) +3303*a(n-42) +1366*a(n-43) +342*a(n-44) +18*a(n-45) -72*a(n-46) for n>50
EXAMPLE
Some solutions for n=4
..1..0..2..1..2..2....2..1..2..2..2..2....1..2..2..2..1..2....2..1..2..2..2..1
..0..2..1..2..2..1....2..2..2..2..2..1....2..2..2..2..2..1....1..2..2..2..2..2
..2..1..2..2..1..2....2..2..2..2..2..2....2..2..2..2..2..2....2..2..2..2..1..2
..1..2..2..1..2..2....2..2..2..2..2..2....1..2..2..2..2..2....2..2..2..2..2..2
..2..2..1..2..2..1....1..2..2..2..2..2....2..1..2..2..1..2....2..1..2..2..2..2
..2..1..2..2..1..0....2..2..1..2..2..2....0..2..1..2..2..2....2..2..2..1..2..2
CROSSREFS
Sequence in context: A332180 A160034 A273811 * A031599 A265984 A332848
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 12 2014
STATUS
approved