A265874 Number of nX2 integer arrays with each element equal to the number of horizontal, vertical and antidiagonal neighbors less than itself.

3, 25, 137, 2084, 14854, 136969, 1288011, 10892624, 100704674, 892590671, 7950193635, 71567811760, 637199515774, 5707339035978, 51047992073786, 456183576476042, 4081865897450479, 36493975748298209, 326363143849784453

Offset

1,1

Comments

Column 2 of A265878.

Links

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

Formula

Empirical: a(n) = 3*a(n-1) +21*a(n-2) +203*a(n-3) +238*a(n-4) +4932*a(n-5) -849*a(n-6) +1928*a(n-7) -121174*a(n-8) -213452*a(n-9) -1661362*a(n-10) -1851417*a(n-11) +1090499*a(n-12) +11973623*a(n-13) +3597843*a(n-14) +4813209*a(n-15) -34905904*a(n-16) +30566100*a(n-17) -51580886*a(n-18) +30604488*a(n-19) -34706660*a(n-20) +227606392*a(n-21) +121796739*a(n-22) -26131615*a(n-23) -219798407*a(n-24) -65796547*a(n-25) +157754498*a(n-26) +21801560*a(n-27) -33218767*a(n-28) +34577383*a(n-29) +11740953*a(n-30) -15006230*a(n-31) -5174032*a(n-32) +8271454*a(n-33) -2211321*a(n-34) +302698*a(n-35) +259499*a(n-36) +410728*a(n-37) -251580*a(n-38) +104016*a(n-39) -18192*a(n-40) +1024*a(n-41)

Example

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

Crossrefs

Cf. A265878.

Sequence in context: A243228 A112495 A034578 * A144646 A308417 A277520

Adjacent sequences: A265871 A265872 A265873 * A265875 A265876 A265877

Keyword

nonn

Author

R. H. Hardin, Dec 17 2015

Status

approved