1,4

An intercalate is a 2 X 2 subsquare of a Latin square. a(10) >= 125, a(11) >= 172, a(12) >= 324.

R. Bean, Critical sets in Latin squares and associated structures, Ph.D. Thesis, The University of Queensland, 2001.

K. Heinrich and W. Wallis, The maximum number of intercalates in a Latin square, Combinatorial Math. VIII, Proc. 8th Australian Conf. Combinatorics, 1980, 221-233.

I. Wanless, Private communication, 2003.

Index entries for sequences related to Latin squares and rectangles

a(2^n) = n^2(n-1)/4; a(2^n-1) = n(n-1)(n-3)/4

Cf. A091323, A090741.

Sequence in context: A004477 A166206 A040137 this_sequence A081987 A047709 A002911

Adjacent sequences: A092234 A092235 A092236 this_sequence A092238 A092239 A092240

hard,nonn

Richard Bean (rwb(AT)eskimo.com), Feb 17 2004