Poly-Bernoulli numbers B_n^(k) with k=-3.

Terms

a(0) =1a(1) =8a(2) =46a(3) =230a(4) =1066a(5) =4718a(6) =20266a(7) =85310a(8) =354106a(9) =1455278a(10) =5938186a(11) =24104990a(12) =97478746a(13) =393095438a(14) =1581931306a(15) =6356390270a(16) =25511588986a(17) =102304505198a(18) =409992599626