

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, 3X3 Semimagic square retaining 4 units of water
Hugo Pfoertner, 4X4 Semimagic square retaining 22 units of water
Walter Trump, 5X5 Semimagic square retaining 78 units of water
Hugo Pfoertner, 6X6 Semimagic square retaining 199 units of water
Hugo Pfoertner, 7X7 Semimagic square retaining 424 units of water
Hugo Pfoertner, 8X8 Semimagic square retaining 814 units of water
Hugo Pfoertner, 9X9 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



