A fourth-order linear divisibility sequence: a(n) := (3^n + 1)*(3^(3*n) - 1)/( (3 + 1)*(3^3 - 1)).

A238540

A fourth-order linear divisibility sequence: a(n) := (3^n + 1)*(3^(3*n) - 1)/( (3 + 1)*(3^3 - 1)).

Terms

    a(0) =1a(1) =70a(2) =5299a(3) =419020a(4) =33664741a(5) =2719393810a(6) =220069738519

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