A123306 Column 0 of triangle A123305.

1, 1, 2, 6, 26, 156, 1234, 12340, 150994, 2204112, 37617314, 738465620, 16451763834, 411281292920, 11427727238034, 350040470610996, 11736423864328466, 428080429306305136, 16893650334361392866

Offset: 0

Author

Paul D. Hanna, Sep 24 2006

Keywords

• nonn

Comments

Triangle T=A123305 is defined by: (column k of T) = (k+1)*(column k of T^2) shifted to have an initial '1'; thus this sequence shift left equals column 0 of T^2.

Crossrefs

Cf. A123305; A123307, A123308, A123309; A123310, A123311.