27323

Appears in sequences

• Composite numbers k that divide Fibonacci(k+1).at n=13A069107
• Odd Fibonacci pseudoprimes: odd composite numbers k such that either (1) k divides Fibonacci(k-1) if k == +-1 (mod 5) or (2) k divides Fibonacci(k+1) if k == +-2 (mod 5).at n=20A081264
• Numbers k that divide Fibonacci(k+1) but do not divide Fibonacci(k) + 1.at n=11A094412
• Semiprimes k that divide Fibonacci(k+1).at n=10A177745
• Composite numbers k that divide both Fibonacci(k+1) and Fibonacci(2k+1)-1.at n=12A182504
• Composite numbers k that divide Fibonacci(k+1) or Fibonacci(k-1).at n=25A182554
• Pairs of numbers a, b for which sigma*(a)=b and sigma(b)-b-1=a, where sigma*(n) is the sum of the anti-divisors of n.at n=10A192292
• G.f.: 1/(1 - x/(1 - x^4/(1 - x^9/(1 - x^16/(1 - x^25/(1 - x^36/(1 -...- x^(n^2)/(1 -...))))))), a continued fraction.at n=34A206739
• Lucas pseudoprimes.at n=25A217120
• Number of length 3+1 0..n arrays with the sum of the maximum of each adjacent pair multiplied by some arrangement of +-1 equal to zero.at n=37A250647
• Partial sums of A263614 starting at n=2.at n=42A263615
• Odd composite integers m such that F(m)^2 == 1 (mod m), where F(m) is the m-th Fibonacci number.at n=35A337231
• Triangle T(n,k) defined by Sum_{k=1..n} T(n,k)*u^k*x^n/n! = exp(Sum_{n>0} u*d(n)*x^n/n!), where d(n) is the number of divisors of n.at n=38A338870
• Odd composite integers m such that A000032(2*m-J(m,5)) == J(m,5) (mod m), where J(m,5) is the Jacobi symbol.at n=25A339517
• Odd composite integers m such that A001906(m-J(m,5)) == 0 (mod m) and gcd(m,5)=1, where J(m,5) is the Jacobi symbol.at n=41A340097
• Odd composite integers m such that A000045(2*m-J(m,5)) == 1 (mod m), where J(m,5) is the Jacobi symbol.at n=24A340118