39844

Appears in sequences

• Engel expansion of Sum_{k>=0} 1/(8 + k)^k.at n=13A063191
• Number of squarefree integers in closed interval [2^n, -1 + 2*2^n], i.e., among 2^n consecutive numbers beginning with 2^n.at n=16A077643
• Number of permutations p of 1,2,...,n such that the numerator of the continued fraction [p(1); p(2),...,p(n)] is prime.at n=8A078433
• Structured truncated tetrahedral numbers.at n=27A100156
• Admirable Harshad numbers n such that the subtracted divisor is equal to the digital sum of n.at n=18A111948
• G.f.: A(x) = x + A(-x)^2.at n=12A143045
• Number of squarefree integers not exceeding 2^n.at n=16A143658
• Number of isolated vertices in all 3-noncrossing RNA structures on n vertices.at n=11A187255
• Number of permutations of an n X 4 array with each element moving exactly one horizontally or vertically and without 2-loops.at n=7A216796
• T(n,k)=Number of permutations of an nXk array with each element moving exactly one horizontally or vertically and without 2-loops.at n=58A216800
• T(n,k)=Number of permutations of an nXk array with each element moving exactly one horizontally or vertically and without 2-loops.at n=62A216800
• Numbers n such that 2*n + {3, 5, 9, 11} are all primes.at n=32A222960
• 1/(Integral_{x=0..1} x^(x^(x^n)) dx - 1/2), rounded to the nearest integer.at n=41A322009
• Least k such that the k-th squarefree number has exactly n ones in its binary expansion.at n=15A372541