a(n) = (2^prime(n)-2)/prime(n); a(0) = 0 by convention.

A064535

a(n) = (2^prime(n)-2)/prime(n); a(0) = 0 by convention.

Terms

    a(0) =0a(1) =1a(2) =2a(3) =6a(4) =18a(5) =186a(6) =630a(7) =7710a(8) =27594a(9) =364722a(10) =18512790a(11) =69273666a(12) =3714566310a(13) =53634713550a(14) =204560302842

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