A254391 Number of (2+2)X(n+2) 0..1 arrays with every 3X3 subblock diagonal maximum plus antidiagonal maximum nondecreasing horizontally, vertically and ne-to-sw antidiagonally

3372, 35529, 406548, 4711324, 54122833, 623732385, 7193711039, 82923118414, 955995402059, 11022134475890, 127075763475026, 1465081267535444, 16891290642206178, 194743654275922711, 2245245424332506404

Offset

1,1

Comments

Row 2 of A254390

Links

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

Formula

Empirical: a(n) = 13*a(n-1) -7*a(n-2) -43*a(n-3) -860*a(n-4) -920*a(n-5) +15830*a(n-6) -9400*a(n-7) -7539*a(n-8) -98847*a(n-9) +40329*a(n-10) +147709*a(n-11) +83340*a(n-12) +421956*a(n-13) -537724*a(n-14) +204762*a(n-15) -1909934*a(n-16) -520990*a(n-17) +1344182*a(n-18) -2472492*a(n-19) +10604787*a(n-20) +1923137*a(n-21) -6305887*a(n-22) -1207655*a(n-23) -18037820*a(n-24) +3466634*a(n-25) +11862724*a(n-26) +5340110*a(n-27) +12134681*a(n-28) -11925689*a(n-29) -8047471*a(n-30) +1011577*a(n-31) -3455262*a(n-32) +6530290*a(n-33) +1826872*a(n-34) -3037352*a(n-35) +578112*a(n-36) +205440*a(n-37) -198848*a(n-38) +22784*a(n-39) +10496*a(n-40) -1024*a(n-41) for n>42

Example

Some solutions for n=2
..0..0..1..1....0..1..0..1....1..1..1..1....1..0..0..1....1..1..0..1
..1..0..0..1....0..1..1..0....1..1..0..0....1..1..1..1....1..1..0..0
..0..1..1..1....1..1..1..0....1..0..0..0....0..1..1..0....0..1..1..0
..1..0..0..0....0..1..1..0....1..1..0..1....1..0..1..0....1..1..1..1

Crossrefs

Sequence in context: A346025 A178506 A248443 * A254384 A253979 A139779

Adjacent sequences: A254388 A254389 A254390 * A254392 A254393 A254394

Keyword

nonn

Author

R. H. Hardin, Jan 29 2015

Status

approved