OFFSET
1,2
COMMENTS
Partial sums of number of fixed polyominoes with n cells, for n > 0.
LINKS
John Mason, Table of n, a(n) for n = 1..56
FORMULA
a(n) = Sum_{i=1..n} A001168(i).
EXAMPLE
a(6) = 1 + 2 + 6 + 19 + 63 + 216 = 307.
CROSSREFS
KEYWORD
nonn
AUTHOR
Jonathan Vos Post, Apr 23 2010
STATUS
approved