20971519

Appears in sequences

• Woodall (or Riesel) numbers: n*2^n - 1.at n=19A003261
• a(n) = 5*2^(n-1) - 1, n>0, with a(0)=1.at n=23A052549
• a(n) = T(n,1), array T as in A054134.at n=23A054135
• a(n) = 5*2^n - 1.at n=22A153894
• a(n) = 5*4^n - 1.at n=11A156760
• a(n) = 10*8^n - 1.at n=7A198857
• Woodall semiprimes: Semiprimes of the form n*2^n - 1.at n=7A242115
• a(n) is the least integer m > 1 such that n is the largest number of identical digits that can end m^k for positive integer k.at n=21A244364
• Decimal representation of the n-th iteration of the "Rule 155" elementary cellular automaton starting with a single ON (black) cell.at n=12A263245
• Decimal representation of the diagonal from the origin to the corner of the n-th stage of growth of the two-dimensional cellular automaton defined by "Rule 809", based on the 5-celled von Neumann neighborhood.at n=25A286858
• Decimal representation of the diagonal from the origin to the corner of the n-th stage of growth of the two-dimensional cellular automaton defined by "Rule 329", based on the 5-celled von Neumann neighborhood.at n=25A287717
• a(n) = 5*2^n - (-1)^n.at n=22A321643
• Bases where the n-th Goodstein sequence starting in base 3 (instead of base 2) reaches 0.at n=14A349482