1572862
domain: N
Appears in sequences
- a(2*n) = 3*2^n - 2; a(2*n+1) = 2^(n+2) - 2.at n=38A027383
- a(n) = 3*2^n - 2.at n=19A033484
- Add 1, double, add 1, double, etc.at n=38A083416
- Duplicate of A033484.at n=19A099018
- Start with 1, then alternately double or add 2.at n=38A099942
- Numbers m such that phi(sum of the divisors of m) = phi(sum of the distinct prime divisors of m) where phi is the Euler totient function.at n=26A282515
- Numbers m such that phi(sum of divisors of m) = lambda(sum of distinct primes dividing m).at n=13A284202
- Number of bisymmetric, quasitrivial, and order-preserving binary operations on the n-element set {1,...,n}.at n=20A296953
- a(n) = n! * [x^n] (2*x - 4*exp(x) + 3*exp(2*x) + 3) / 2.at n=20A369491