A250946 Number of (4+1)X(n+1) 0..2 arrays with nondecreasing x(i,j)+x(i,j-1) in the i direction and nondecreasing absolute value of x(i,j)-x(i-1,j) in the j direction

1333, 10528, 71014, 444421, 2572787, 14019652, 72722706, 362340909, 1746171891, 8182688256, 37443575402, 167877273621, 739477215669, 3207365341178, 13723656820428, 58018450492133, 242666653153141, 1005288683429826

Offset

1,1

Comments

Row 4 of A250942

Links

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

Formula

Empirical: a(n) = 15*a(n-1) -61*a(n-2) -152*a(n-3) +1682*a(n-4) -1703*a(n-5) -16149*a(n-6) +38870*a(n-7) +75197*a(n-8) -312818*a(n-9) -142144*a(n-10) +1474228*a(n-11) -292298*a(n-12) -4642526*a(n-13) +2703538*a(n-14) +10380008*a(n-15) -8829560*a(n-16) -17038906*a(n-17) +18106086*a(n-18) +20940696*a(n-19) -26095162*a(n-20) -19483676*a(n-21) +27561884*a(n-22) +13797508*a(n-23) -21691685*a(n-24) -7443993*a(n-25) +12756827*a(n-26) +3050176*a(n-27) -5561770*a(n-28) -940583*a(n-29) +1763247*a(n-30) +213658*a(n-31) -392595*a(n-32) -34050*a(n-33) +57780*a(n-34) +3408*a(n-35) -5008*a(n-36) -160*a(n-37) +192*a(n-38)

Example

Some solutions for n=3
..0..0..0..2....0..0..0..2....1..1..1..0....1..1..0..1....1..1..0..2
..0..0..2..0....0..0..1..1....1..2..0..1....0..2..1..0....2..2..2..0
..0..1..1..1....0..0..1..1....1..2..0..1....0..2..1..0....2..2..2..0
..0..1..1..2....1..1..0..2....2..1..1..2....0..2..1..0....2..2..2..0
..0..2..2..1....1..1..2..0....1..2..2..1....1..1..2..1....2..2..2..2

Crossrefs

Sequence in context: A028501 A183646 A250902 * A145494 A234264 A237476

Adjacent sequences: A250943 A250944 A250945 * A250947 A250948 A250949

Keyword

nonn

Author

R. H. Hardin, Nov 28 2014

Status

approved