0,3

Number of 2-dimensional partitions of n where each row is non-squashing.

N. J. A. Sloane and J. A. Sellers, On non-squashing partitions, Discrete Math., 294 (2005), 259-274.

a(4) = 12:

4.31.3.22.2.211.21.2..2.11.11.1

.....1....2.....1..11.1.11.1..1

......................1....1..1

..............................1

211 and 1111 for example are excluded because they would squash.

Cf. A000123, A018819, A001970.

Sequence in context: A082740 A010067 A024458 this_sequence A034763 A121482 A013498

Adjacent sequences: A089289 A089290 A089291 this_sequence A089293 A089294 A089295

nonn

njas, Dec 24 2003