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A254561 Number of (n+2)X(1+2) 0..1 arrays with every 3X3 subblock sum of the four sums of the central row, central column, diagonal and antidiagonal nondecreasing horizontally and vertically 1
512, 2384, 10240, 37200, 116056, 358324, 1029664, 2800912, 7536024, 19539824, 49071028, 122137716, 297265144, 708589765, 1676189792, 3907023789, 8978272228, 20497994769, 46321914076, 103638618227, 230617227832, 509410016859 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Column 1 of A254568
LINKS
FORMULA
Empirical: a(n) = 6*a(n-1) -12*a(n-2) +38*a(n-3) -183*a(n-4) +372*a(n-5) -654*a(n-6) +2508*a(n-7) -5208*a(n-8) +6760*a(n-9) -20358*a(n-10) +43512*a(n-11) -46889*a(n-12) +108378*a(n-13) -241308*a(n-14) +230802*a(n-15) -393975*a(n-16) +933156*a(n-17) -830560*a(n-18) +975804*a(n-19) -2563392*a(n-20) +2214488*a(n-21) -1532964*a(n-22) +4959408*a(n-23) -4373184*a(n-24) +1014144*a(n-25) -6401472*a(n-26) +6289888*a(n-27) +1572336*a(n-28) +4429248*a(n-29) -6288128*a(n-30) -5389632*a(n-31) +990720*a(n-32) +3815040*a(n-33) +7654464*a(n-34) -6015744*a(n-35) -567040*a(n-36) -6564864*a(n-37) +6844416*a(n-38) -1196032*a(n-39) +3508224*a(n-40) -4153344*a(n-41) +1105920*a(n-42) -1081344*a(n-43) +1376256*a(n-44) -425984*a(n-45) +147456*a(n-46) -196608*a(n-47) +65536*a(n-48) for n>50
EXAMPLE
Some solutions for n=4
..1..0..1....1..0..0....0..1..0....0..1..0....1..1..0....1..0..1....1..1..0
..1..0..1....0..0..0....1..0..0....0..0..1....1..0..0....1..0..1....0..0..0
..0..1..1....1..0..0....1..0..0....1..1..1....1..0..0....0..0..1....1..0..1
..1..1..0....1..0..0....1..0..1....1..1..0....1..1..0....1..0..1....1..0..1
..0..1..1....1..0..0....1..0..0....1..1..1....1..1..1....1..1..0....1..0..0
..1..0..1....0..0..1....1..1..1....1..1..1....1..0..1....1..1..0....1..1..0
CROSSREFS
Sequence in context: A258522 A258519 A254568 * A254907 A257209 A254900
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 01 2015
STATUS
approved

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Last modified March 28 11:58 EDT 2024. Contains 371241 sequences. (Running on oeis4.)