A115982 - OEIS

%I #3 Mar 31 2012 13:23:37

%S 0,0,0,1,3,10,23,54,112,228,437,826,1499,2685,4688,8079,13668,22875,

%T 37738,61676,99672,159742,253681,399962,625741,972756,1502302,2306988,

%U 3522492,5351239,8088469,12170163,18229411,27192571

%N Number of planar partitions that are not corners.

%C a(n) can also be approximated by considering A000094 since A000094(n) = A000041(n) - n = 0 0 0 1 2 5 8 14 21 32 ... with partial sums 0 0 0 1 3 8 16 30 51 83 ... which counts many of the initial cases. The remaining cases form 0 0 0 0 0 2 7 24 ... counting for n=6, 22/11 and 21/21.

%F a(n) = A000219(n) - A006330(n)

%e The planar partitions begin 1 3 6 13 24 48 ... A000219 with corners 1 3 6 12 21 38 ... A006330; therefore the present sequence begins 0 0 0 1 3 10 ...

%Y Cf. A000219, A006330, A000041, A000094.

%K easy,nonn

%O 1,5

%A _Alford Arnold_, Feb 17 2006

%E Edited with additional terms by _Franklin T. Adams-Watters_, Mar 10 2006