A268855 a(n) = smallest magic sum of any 3 X 3 magic square which contains exactly n squares.

30, 21, 18, 15, 39, 120, 435, 541875

Offset

0,1

Comments

a(7) = 8*A268854(7) + 3.

If a(8) exists, and the central element is a square, then a(8) > 10^21. - Arkadiusz Wesolowski, Sep 01 2024

Links

Table of n, a(n) for n=0..7.

Andrew Bremner, On squares of squares II, Acta Arithmetica 99 (2001), pp. 289-308.

Multimagic Squares, Magic squares of squares

The Prime Puzzles and Problems Connection, Problem 63

The Prime Puzzles and Problems Connection, Puzzle 79

Arkadiusz Wesolowski, Examples of these magic squares

Wikipedia, Magic square

Index entries for sequences related to magic squares

Crossrefs

Cf. A221669, A268854, A268856, A269231, A375459.

Sequence in context: A193220 A040872 A361029 * A117749 A283621 A100935

Adjacent sequences: A268852 A268853 A268854 * A268856 A268857 A268858

Keyword

nonn,fini,hard,more

Author

Arkadiusz Wesolowski, Feb 14 2016

Status

approved