Triangle arising in the computation of hypersigma, definition 2 (A191161).

Terms

a(0) =1a(1) =1a(2) =1a(3) =1a(4) =4a(5) =1a(6) =1a(7) =6a(8) =18a(9) =1a(10) =1a(11) =8a(12) =36a(13) =104a(14) =1a(15) =1a(16) =10a(17) =60a(18) =260a(19) =750a(20) =1a(21) =1a(22) =12a(23) =90a(24) =520a(25) =2250a(26) =6492a(27) =1a(28) =1a(29) =14