131071

Properties

Appears in sequences

• a(n) = 2^n - 1. (Sometimes called Mersenne numbers, although that name is usually reserved for A001348.)at n=17A000225
• Mersenne primes (primes of the form 2^n - 1).at n=5A000668
• Table T(n,k) in which n-th row lists prime factors of 2^n - 1 (n >= 2), with repetition.at n=35A001265
• Mersenne numbers: 2^p - 1, where p is prime.at n=6A001348
• a(n) = least primitive factor of 2^(2n+1) - 1.at n=8A002184
• a(n) = largest noncomposite factor of 2^(2n+1) - 1.at n=25A002588
• a(n) = largest noncomposite factor of 2^(2n+1) - 1.at n=8A002588
• Numerators of the Taylor coefficients of (e^x-1)^2.at n=16A002678
• Largest prime factor of n-th Mersenne number (A001348(n)).at n=6A003260
• Primes of form (p^x - 1)/(p^y - 1), p prime.at n=27A003424
• Divisors of 2^34 - 1.at n=3A003541
• Class 1+ primes: primes of the form 2^i*3^j - 1 with i, j >= 0.at n=32A005105
• Largest prime factor of 2^n - 1.at n=32A005420
• Largest prime factor of 2^n - 1.at n=15A005420
• Number of nonzero coefficients of order n in Baker-Campbell-Hausdorff expansion.at n=19A005489
• Mersenne numbers with at most 2 prime factors.at n=6A006515
• Numbers k such that k and k+1 are prime powers.at n=12A006549
• a(n) = (n+3)*2^n - 1.at n=14A006589
• If n mod 4 = 0 then 2^(n-1)+1 elif n mod 4 = 2 then 2^(n-1)-1 else 2^(n-1).at n=17A007679
• Numbers n such that game of n X n Button Madness need have no solution; this lists only the primitive elements of the set.at n=18A007802