A141824 Antidiagonals of table A047888 (which counts longest increasing subsequences and pattern avoidances).

1, 2, 4, 9, 24, 75, 269, 1095, 5039, 26084, 150356, 952526, 6553011, 48553418, 385693800, 3277413802, 29741002168, 287555932433, 2952769116993, 32079033571080, 367336668735826, 4419518218479215, 55733223965845539, 735448682261126767, 10142738983005750681

Offset: 1

Author

Alford Arnold, Jul 08 2008

Keywords

• nonn

Comments

Note that:

A000108 avoids string "123"

A005808 avoids string "1234"

A047889 avoids string "12345"

Note also that the left half and central diagonal of A047888 are partial sums of table A047874.

Examples

			We can write A141824(n) = 1 2 4 9 24 ... because A047888 begins
  1;
  1,  1;
  1,  2,  1;
  1,  5,  2,  1;
  1, 14,  6,  2,  1;
etc.
		

Crossrefs

Cf. A000108 (Catalan numbers), A005808, A047889, A047874.

Extensions

a(12)-a(25) from Alois P. Heinz, Apr 10 2012