274877382656
domain: N
Appears in sequences
- a(n) = 4^n - 2^n.at n=19A020522
- Numbers k such that the sums of the odd and even aliquot parts of k both divide k.at n=7A065125
- Numbers k such that there is a proper divisor d of k satisfying sigma(d)=k.at n=24A081756
- Admirable oblong numbers.at n=11A109547
- Twice even perfect numbers. Also a(n) = M(n)*(M(n)+1), where M(n) is the n-th Mersenne prime A000668(n).at n=6A139256
- Numbers k such that the maximal prime power divisors of k form a nontrivial run of integers.at n=14A141808
- Denominator of ez(n-1)*n!/(4^n-2^n) where ez(n) is the n-th coefficient of sec(t)+tan(t) for n>0, a(0) = 1.at n=19A193473
- a(n) = 4*16^n - 2*4^n.at n=9A193475
- The denominators of the Bernoulli secant numbers at odd indices.at n=9A193476
- Numbers k such that the sum of reciprocals of even divisors of k is an integer.at n=15A224832
- Numbers that can be expressed as the product of largest odd proper divisor and the sum of odd proper divisors.at n=22A225880
- Oblong numbers n such that sigma(n) is a triangular number.at n=26A256150
- Decimal representation of the diagonal from the corner to the origin of the n-th stage of growth of the two-dimensional cellular automaton defined by "Rule 205", based on the 5-celled von Neumann neighborhood.at n=37A286696
- Sum of divisors of the multiply-perfect numbers.at n=24A307741
- a(n) = denominator(n / (4^n - 2^n)) for n > 0 and a(0) = 1.at n=19A336899
- a(n) = denominator(((i^n * PolyLog(1 - n, -i) + (-i)^n * PolyLog(1 - n, i))) / (4^n - 2^n)) if n > 0 and a(0) = 1. Here i denotes the imaginary unit.at n=19A342319
- Numbers k such that k | A328258(k).at n=13A348584
- a(n) is the smallest multiple k of 2^n such that |sigma(k) - 2*k| = 2^n, where sigma = A000203.at n=19A363285
- a(n) = n * (4^n - 2^n) / Clausen(n, 0).at n=19A363402