A059578 Variation of Boustrophedon transform applied to 1,1,1,1,... Fill an array by diagonals, all in the 'up' direction. The first column is 1,1,1,1,.... For the next element of a diagonal, add to the previous element the elements of the row and the column the new element is in. The first row gives a(n).
1, 2, 7, 30, 147, 792, 4559, 27500, 171645, 1099388, 7185101, 47724494, 321225165, 2186177302, 15018795171, 104011496474, 725373340023, 5089785834004, 35907469451787, 254541483884544, 1812185157383017, 12951828431246472, 92893383046741073, 668383820775639066
Offset: 1
Examples
The array begins 1 2 7 30 ... 1 4 20 ... 1 8 ... 1 ...
Extensions
More terms from Sean A. Irvine, Sep 29 2022