A213799
Number of n X n 0..7 symmetric arrays with every row summing to floor(n*7/2).
Original entry on oeis.org
1, 8, 226, 52544, 84662388, 1012226679296, 87098380004205128
Offset: 1
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
A213804
Number of 6 X 6 0..n symmetric arrays with all rows summing to 3*n.
Original entry on oeis.org
1, 1760, 526443, 34725760, 932587453, 13937940952, 138198204339, 1012226679296, 5875958390949, 28376054552968, 118033137259563, 433946033473016, 1438074947544977, 4362051703339832, 12258717265789491, 32233542519648928, 79941392042719253, 188248433874383736, 423266982431567911
Offset: 0
Some solutions for n=4
..2..4..0..4..0..2....2..4..3..3..0..0....2..1..3..0..2..4....2..0..2..3..1..4
..4..1..2..4..0..1....4..3..3..1..0..1....1..2..4..3..0..2....0..4..3..3..1..1
..0..2..3..0..4..3....3..3..3..2..0..1....3..4..1..2..0..2....2..3..3..0..3..1
..4..4..0..2..0..2....3..1..2..0..4..2....0..3..2..3..3..1....3..3..0..0..3..3
..0..0..4..0..4..4....0..0..0..4..4..4....2..0..0..3..4..3....1..1..3..3..2..2
..2..1..3..2..4..0....0..1..1..2..4..4....4..2..2..1..3..0....4..1..1..3..2..1
a(0)=1 prepended and terms a(12) and beyond from
Andrew Howroyd, Apr 07 2020
A213805
Number of 7 X 7 0..n symmetric arrays with all rows summing to floor(n*7/2).
Original entry on oeis.org
1, 35150, 133721189, 46259653191, 4893373431575, 212962858290086, 5406415387421647, 87098380004205128, 1034209337638242207, 9323807379913081007, 69112259378483785503, 425995640129266136995, 2291562702094516094937, 10801522912361264775797, 46064488469672007773725
Offset: 0
Some solutions for n=4
..2..2..1..2..2..4..1....1..2..2..4..2..0..3....4..4..0..0..3..0..3
..2..4..4..4..0..0..0....2..0..2..3..1..2..4....4..4..0..2..3..0..1
..1..4..3..3..3..0..0....2..2..4..1..4..0..1....0..0..1..1..4..4..4
..2..4..3..4..0..0..1....4..3..1..1..0..2..3....0..2..1..0..3..4..4
..2..0..3..0..1..4..4....2..1..4..0..2..4..1....3..3..4..3..0..1..0
..4..0..0..0..4..2..4....0..2..0..2..4..4..2....0..0..4..4..1..3..2
..1..0..0..1..4..4..4....3..4..1..3..1..2..0....3..1..4..4..0..2..0
a(0)=1 prepended and terms a(6) and beyond from
Andrew Howroyd, Apr 07 2020
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