A257356 Number of (n+2)X(3+2) 0..1 arrays with no 3x3 subblock diagonal sum equal to the antidiagonal sum or central row sum less than the central column sum

3108, 6724, 17056, 45796, 112236, 234256, 475608, 1136356, 2763008, 5914624, 12499644, 29203216, 68721712, 150160516, 325035968, 747038224, 1727481692, 3815779984, 8381071304, 19092054276, 43659093360, 97078357476, 215135035828

Offset

1,1

Comments

Column 3 of A257361

Links

R. H. Hardin, Table of n, a(n) for n = 1..210

Formula

Empirical: a(n) = 2*a(n-3) +16*a(n-4) +8*a(n-5) +4*a(n-6) +2*a(n-7) +18*a(n-8) +6*a(n-9) -4*a(n-10) -18*a(n-11) -141*a(n-12) -60*a(n-13) +48*a(n-14) +18*a(n-15) -117*a(n-16) -66*a(n-17) +48*a(n-19) +279*a(n-20) +108*a(n-21) -12*a(n-22) -12*a(n-23) +15*a(n-24) +36*a(n-25) +16*a(n-26) -6*a(n-27) -36*a(n-28) -8*a(n-29) -4*a(n-30) -2*a(n-31) -a(n-32) -2*a(n-33) +a(n-36) for n>39

Example

Some solutions for n=4
..1..1..1..0..0....1..1..1..0..1....0..0..0..1..0....0..0..1..0..0
..0..1..1..0..0....1..0..0..1..1....0..1..1..0..1....1..1..1..0..0
..1..0..0..1..1....1..0..0..1..1....1..1..0..1..1....1..1..0..0..1
..1..0..0..1..1....1..1..1..0..0....1..0..1..1..0....1..0..0..1..1
..0..1..1..0..1....1..1..1..0..0....1..1..1..0..1....1..0..1..1..1
..1..1..1..1..1....1..1..0..1..1....1..1..0..1..0....1..1..1..1..1

Crossrefs

Cf. A257361

Sequence in context: A234265 A090056 A229410 * A187593 A230923 A137839

Adjacent sequences: A257353 A257354 A257355 * A257357 A257358 A257359

Keyword

nonn

Author

R. H. Hardin, Apr 20 2015

Status

approved