3^(p-1)-2^(p+1) for primes p > 3.A2399263^(p-1)-2^(p+1) for primes p > 3.Terms a(0) =17a(1) =473a(2) =54953a(3) =515057a(4) =42784577a(5) =386371913a(6) =31364282393External referencesoeis: A239926