18609

Appears in sequences

• Fibonacci sequence beginning 3, 17.at n=16A022127
• Number of partitions satisfying cn(1,5) + cn(4,5) <= cn(2,5) + cn(3,5).at n=40A039894
• Indices of primes in sequence defined by A(0) = 71, A(n) = 10*A(n-1) + 31 for n > 0.at n=13A101139
• Numbers n such that 9*10^n + 5*R_n - 4 is prime, where R_n = 11...1 is the repunit (A002275) of length n.at n=19A103100
• a(n) = 5n^4 - 4n^3 + 3n^2 - 2n + 1.at n=8A131466
• Numbers k such that 2*(3^k-2*k)+1 is prime.at n=12A195815
• a(n) = floor((n + 1/2)^3).at n=26A219085
• Floor(compositorial(n) / n!), that is, floor(A036691(n) / A000142(n)).at n=12A233447
• Smallest positive integer solution x = a(n) of (3^4)*x - 2^n*y = 1 for n >= 0.at n=15A239130
• Smallest positive integer solution x = a(n) of (3^4)*x - 2^n*y = 1 for n >= 0.at n=16A239130
• E.g.f.: Sum_{n>=0} x^n * (1 + x^n)^n * exp(2*x^(n+1)) / n!.at n=7A259202
• Numbers k such that the decimal number concat(4,k) is a square.at n=36A273359