6193152
domain: N
Appears in sequences
- Theta series of D*_14 lattice.at n=19A022067
- Numbers m such that uphi(sigma(m)) = 2m, where the unitary phi function (A047994) is defined by: if x = p1^r1*p2^r2*p3^r3*... then uphi(x) = (p1^r1 - 1)*(p2^r2 - 1)*(p3^r3 - 1)*...at n=22A030165
- Triangle read by rows: (i,j)-th entry is binomial(i,j)*3^(i-j)*8^j.at n=33A038226
- Triangle whose (i,j)-th entry is binomial(i,j)*8^(i-j)*3^j.at n=30A038281
- Maximal number of divisors of any n-digit number.at n=27A066150
- 19-almost primes (generalization of semiprimes).at n=24A069280
- a(1) = 1, a(2) = (2*1)/1 = 2. a(n+1) = (n+1)*a(n) divided by the largest prime divisor of a(n).at n=20A100773
- Triangular array read by rows. T(n,k) is the number of rooted labeled trees on n nodes such that the root node has degree k. n>=2, 1<=k<=n-1.at n=30A206429
- Number of nonisomorphic unfoldings of the n-th Johnson solid.at n=21A343210