OFFSET
0,2
COMMENTS
A domino with short side length k has dimensions k X 2k.
Terms a(5) to a(13) were found by Erich Friedman in 1998, a(14) to a(19) by Erich Friedman in January 2004.
a(n) >= ceiling(sqrt(n*(n + 1)*(2n + 1)/3)).
LINKS
Erich Friedman, Dominoes in Squares
EXAMPLE
Illustration:
.
. - - a - - - a a - - - - - - - - a a b b
. a a a - - - b b b b - - c c c c c c b b
. b b b b b b b b - - c c c c c c b b
. b b b b c c c c c c c c c c c c b b
. c c c c c c d d d d d d d d
. c c c c c c d d d d d d d d
. d d d d d d d d
. d d d d d d d d
.
. 2 4 6 8
.
CROSSREFS
KEYWORD
nonn,hard,more
AUTHOR
Ivan Panchenko, Feb 15 2014
STATUS
approved