Row sums of triangle A144270 (called S2hat(-1)).

A144271

Row sums of triangle A144270 (called S2hat(-1)).

Terms

    a(0) =1a(1) =2a(2) =5a(3) =21a(4) =129a(5) =1099a(6) =11647a(7) =148292a(8) =2190302a(9) =36842892a(10) =694276152a(11) =14488348603a(12) =331537914373

External references