Numerators of poly-Bernoulli numbers B_n^(k) with k=2.

Terms

a(0) =1a(1) =1a(2) =-1a(3) =-1a(4) =7a(5) =1a(6) =-38a(7) =-5a(8) =11a(9) =7a(10) =-3263a(11) =-15a(12) =13399637a(13) =7601a(14) =-8364a(15) =-91a(16) =1437423473a(17) =3617a(18) =-177451280177a(19) =-745739a(20) =166416763419a(21) =3317609a(23) =-5981591a(25) =5436374093a(27) =-213827575