Coefficient of x^n in the expansion of ( 1/(1-x)^2 * (1+x^2) )^n.

A370242

Coefficient of x^n in the expansion of ( 1/(1-x)^2 * (1+x^2) )^n.

Terms

    a(0) =1a(1) =2a(2) =12a(3) =74a(4) =480a(5) =3202a(6) =21756a(7) =149746a(8) =1040640a(9) =7285538a(10) =51307212a(11) =363057114a(12) =2579270304a(13) =18385404546a(14) =131429288828a(15) =941857237474

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