E.g.f.: exp(2 * (exp(x) - 1 - x - x^2 / 2 - x^3 / 6 - x^4 / 24)).

Terms

a(0) =1a(1) =0a(2) =0a(3) =0a(4) =0a(5) =2a(6) =2a(7) =2a(8) =2a(9) =2a(10) =506a(11) =1850a(12) =5018a(13) =12014a(14) =26886a(15) =1066782a(16) =8193070a(17) =42723722a(18) =185108514a(19) =719359762a(20) =10426744914a(21) =118490840686a(22) =976376930502