38799

Appears in sequences

• Odd composite n such that phi(n) * sigma(n) is one less than a square.at n=21A015722
• Least number k such that k*p(n)*(k*p(n)+1)-1, k*p(n)*(k*p(n)+1)+1, k*p(n)*(k*p(n)+3)-1 and k*p(n)*(k*p(n)+3)+1 are all primes, two pairs of twin primes, with p(i) = i-th prime.at n=35A139638
• Triangular array read by rows: row n shows the coefficients of the polynomial u(n) = c(0) + c(1)*x + ... + c(n)*x^(n) which is the numerator of the n-th convergent of the continued fraction [k, k, k, ... ], where k = (x + 1)/(x + 2).at n=49A231774
• Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 163", based on the 5-celled von Neumann neighborhood.at n=38A270455
• a(n) = (3 + 2*n - 3*n^2 + 4*n^3 - 3*((-1 + n) mod 2))/6.at n=38A304487
• Numbers k such that both k and k+1 are not exponentially squarefree numbers.at n=28A342188
• a(1) = 1; a(n) = Sum_{k=1..ceiling(n/2)} a(k) * a(n-k).at n=14A348530
• Numbers k such that k and k+1 both have the same number of squarefree divisors and powerful divisors.at n=14A360904