OFFSET
0,2
LINKS
Erich Friedman, L's in Squares
FORMULA
a(n) = A211372(n)^2
EXAMPLE
Illustration:
.
. a - b b a - - - - b b b b - - - - - - - - a b b
. a a b b a a c c c b b b b - - - - - - - a a b b
. b b b b c c c b b a a - - - - - - - b b b b
. b b b b c c c b b a - d d d d - - - b b b b
. c c c c c c - d d d d - c c c c c c
. c c c c c c - d d d d - c c c c c c
. c c c c c c - d d d d - c c c c c c
. d d d d d d d d c c c
. d d d d d d d d c c c
. d d d d d d d d c c c
. d d d d d d d d - - -
.
. 4 16 49 121
.
CROSSREFS
KEYWORD
nonn,hard,more
AUTHOR
Ivan Panchenko, Feb 16 2014
STATUS
approved