A213799 Number of n X n 0..7 symmetric arrays with every row summing to floor(n*7/2).

1, 8, 226, 52544, 84662388, 1012226679296, 87098380004205128

Offset

1,2

Comments

Column 7 of A213800.

Links

Table of n, a(n) for n=1..7.

Example

Some solutions for n=4:
..4..4..5..1....7..0..0..7....2..3..7..2....1..1..5..7....5..4..4..1
..4..6..0..4....0..3..6..5....3..4..0..7....1..2..4..7....4..0..3..7
..5..0..2..7....0..6..6..2....7..0..5..2....5..4..5..0....4..3..2..5
..1..4..7..2....7..5..2..0....2..7..2..3....7..7..0..0....1..7..5..1

Crossrefs

Cf. A213800.

Sequence in context: A220546 A189445 A193786 * A316809 A299655 A033508

Adjacent sequences: A213796 A213797 A213798 * A213800 A213801 A213802

Keyword

nonn,more

Author

R. H. Hardin, Jun 20 2012

Status

approved