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A253930
Number of (n+2)X(3+2) 0..1 arrays with every 3X3 subblock diagonal sum plus antidiagonal sum nondecreasing horizontally and vertically
1
8392, 30184, 124496, 451721, 992616, 2326216, 4928792, 8796936, 15429736, 25901691, 41279336, 64590680, 98433380, 147871688, 219336822, 319580553, 459762302, 656093206, 925811194, 1292791666, 1788288642, 2455569322
OFFSET
1,1
COMMENTS
Column 3 of A253935
FORMULA
Empirical: a(n) = 5*a(n-1) -12*a(n-2) +20*a(n-3) -20*a(n-4) -4*a(n-5) +54*a(n-6) -118*a(n-7) +161*a(n-8) -125*a(n-9) -8*a(n-10) +216*a(n-11) -425*a(n-12) +509*a(n-13) -398*a(n-14) +78*a(n-15) +370*a(n-16) -770*a(n-17) +972*a(n-18) -852*a(n-19) +417*a(n-20) +195*a(n-21) -804*a(n-22) +1188*a(n-23) -1230*a(n-24) +918*a(n-25) -336*a(n-26) -336*a(n-27) +918*a(n-28) -1230*a(n-29) +1188*a(n-30) -804*a(n-31) +195*a(n-32) +417*a(n-33) -852*a(n-34) +972*a(n-35) -770*a(n-36) +370*a(n-37) +78*a(n-38) -398*a(n-39) +509*a(n-40) -425*a(n-41) +216*a(n-42) -8*a(n-43) -125*a(n-44) +161*a(n-45) -118*a(n-46) +54*a(n-47) -4*a(n-48) -20*a(n-49) +20*a(n-50) -12*a(n-51) +5*a(n-52) -a(n-53) for n>83
Empirical polynomial of degree 13 plus a quasipolynomial of degree 8 with period 24 for n>30 (see link above)
EXAMPLE
Some solutions for n=3
..0..0..0..1..1....0..0..0..0..0....0..0..1..1..0....0..1..0..0..1
..0..0..0..0..1....0..0..0..1..0....0..0..0..1..1....0..0..0..0..1
..0..1..1..1..1....0..0..0..1..0....0..1..1..1..0....0..0..1..1..1
..0..1..1..1..0....0..0..0..1..1....1..1..1..1..1....1..0..0..0..0
..1..0..1..1..0....1..0..1..1..1....1..1..1..0..1....0..1..1..0..1
CROSSREFS
Sequence in context: A252087 A253836 A253843 * A295469 A232300 A214117
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 19 2015
STATUS
approved