A266056 Number of 2Xn integer arrays with each element equal to the number of horizontal and antidiagonal neighbors less than or equal to itself.

1, 7, 12, 58, 598, 4427, 26350, 164148, 1074794, 7035874, 45524948, 294270860, 1906419263, 12357270209, 80067019748, 518700090254, 3360509757482, 21772676551545, 141063777857884, 913934658637407, 5921269752932641

Offset

1,2

Comments

Row 2 of A266055.

Links

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

Formula

Empirical: a(n) = 3*a(n-1) +11*a(n-2) +51*a(n-3) +156*a(n-4) +141*a(n-5) -429*a(n-6) -2785*a(n-7) -5505*a(n-8) -4470*a(n-9) +6355*a(n-10) +33613*a(n-11) +32025*a(n-12) -21483*a(n-13) -43190*a(n-14) -23519*a(n-15) -2201*a(n-16) +16965*a(n-17) +9808*a(n-18) -2953*a(n-19) -715*a(n-20) +1191*a(n-21) -528*a(n-22) -3*a(n-23) +143*a(n-24) -39*a(n-25) +15*a(n-26)

Example

Some solutions for n=4
..1..0..1..2....0..3..3..0....0..3..0..2....1..0..2..2....0..2..3..0
..1..3..1..1....0..3..3..0....0..3..0..1....1..3..1..0....2..0..3..0

Crossrefs

Cf. A266055.

Sequence in context: A192779 A108238 A038278 * A083335 A372734 A358782

Adjacent sequences: A266053 A266054 A266055 * A266057 A266058 A266059

Keyword

nonn

Author

R. H. Hardin, Dec 20 2015

Status

approved