

A201127


Maximum water retention of a semimagic square of order n.


4




OFFSET

3,1


COMMENTS

The same rules as for A201126 apply, but with the magic conditions for both diagonals of the number square removed.
a(10) >= 2280.  Hugo Pfoertner, May 19 2012


LINKS

Table of n, a(n) for n=3..9.
Hugo Pfoertner, 3 X 3 Semimagic square retaining 4 units of water
Hugo Pfoertner, 4 X 4 Semimagic square retaining 22 units of water
Walter Trump, 5 X 5 Semimagic square retaining 78 units of water
Hugo Pfoertner, 6 X 6 Semimagic square retaining 199 units of water
Hugo Pfoertner, 7 X 7 Semimagic square retaining 424 units of water
Hugo Pfoertner, 8 X 8 Semimagic square retaining 814 units of water
Hugo Pfoertner, 9 X 9 Semimagic square retaining 1410 units of water
Wikipedia, Water retention on mathematical surfaces


EXAMPLE

(7 6 2)
(5 1 9)
(3 8 4)
is a semimagic square. The midside bricks with heights 6, 5, 9, 8 form a wall around the central hole with bottom height 1. Water poured upon the square will fill the central pond until overflowing via the left brick of height 5. Thus 4 units of water will be retained.


CROSSREFS

Cf. A201126 (water retention of magic squares).
Sequence in context: A241689 A052149 A062966 * A259709 A078155 A237530
Adjacent sequences: A201124 A201125 A201126 * A201128 A201129 A201130


KEYWORD

nonn,hard,nice


AUTHOR

Hugo Pfoertner, Dec 03 2011


STATUS

approved



