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A123309
Column 3 of triangle A123305.
7
1, 4, 32, 336, 4256, 63072, 1076128, 20900032, 457645984, 11201485632, 304074996512, 9089787596288, 297305835048096, 10578368788224320, 407327197600166304, 16894650230806939776, 751638529171350907808
OFFSET
0,2
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 shifted left equals 4 times column 3 of T^2 (matrix square of A123305).
CROSSREFS
KEYWORD
nonn
AUTHOR
Paul D. Hanna, Sep 25 2006
STATUS
approved