18819
domain: N
Appears in sequences
- Numbers m such that 3*2^m - 1 is prime.at n=34A002235
- Row sums of triangle defined in A095181.at n=16A160915
- Numbers of the form x^2 + y^2 + z^2 = phi(x*y*z) + sigma(x*y*z).at n=26A173792
- a(n) = (prime(n) - 1)*(prime(n+1) - 1)/2 + 3.at n=43A201498
- Molien series for invariants of finite Coxeter group A_12.at n=52A266781
- Numbers n such that n * x/(x-1) produces a rotation of the digits in n for some value of x.at n=21A288669
- Numbers k such that (k*2^d - 1)*(d*2^k - 1) is semiprime for some divisor d of k.at n=44A382646