Diagonal sums of exponential Riordan array [1+x*tan(x/2),x], A166353.

A166355

Diagonal sums of exponential Riordan array [1+x*tan(x/2),x], A166353.

Terms

    a(0) =1a(1) =2a(2) =5a(3) =15a(4) =64a(5) =443a(6) =4887a(7) =78996a(8) =1745995a(9) =50333929a(10) =1829758158a(11) =81753825477

External references