66755

Appears in sequences

• a(n) = 2^n - 1 + 2*Fibonacci(n-1).at n=15A060161
• Denominators of the convergents of the continued fraction for L(3, chi4), where L(s, chi4) is the Dirichlet L-function for the non-principal character modulo 4.at n=9A153074
• Numbers k such that R_(k+2) + 6*10^k is prime, where R_k = 11...1 is the repunit (A002275) of length k.at n=23A256932