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

Author

Arkadiusz Wesolowski, Feb 14 2016

Keywords

• nonn
• fini
• hard
• more

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

• 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.