1,3

a(n)=(-1)^(n+1)*n*A083321(n). G.f.: 2x^3(4-21x+36x^2-21x^3)/((1-x)^2*(1-3x)^2*(1-2x)^2). [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Dec 12 2008]

Cf. A152691

Sequence in context: A085537 A085540 A122657 this_sequence A037966 A091433 A081899

Adjacent sequences: A152689 A152690 A152691 this_sequence A152693 A152694 A152695

nonn

Vladimir Orlovsky (4vladimir(AT)gmail.com), Dec 10 2008