Main diagonal of the triangular array A161135.

Terms

a(0) =1a(1) =2a(2) =5a(3) =9a(4) =37a(5) =86a(6) =232a(7) =748a(8) =932a(9) =2865a(10) =17761a(11) =109780a(12) =249840a(13) =1190787a(14) =3869645a(15) =6479631a(16) =69445201a(17) =75334942