(1/p)*(M(p)-1) where p runs through the odd primes and M(p) = A001006(p) is the p-th Motzkin number.

A086400

(1/p)*(M(p)-1) where p runs through the odd primes and M(p) = A001006(p) is the p-th Motzkin number.

Terms

    a(0) =1a(1) =4a(2) =18a(3) =527a(4) =3218a(5) =138634a(6) =957857a(7) =49120018a(8) =20473889132a(9) =156766505690

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