121500

Appears in sequences

• Integers of the form Product p_j^k_j = Product k_j^p_j; p_j in A000040.at n=15A008478
• Triangle whose (i,j)-th entry is binomial(i,j)*3^(i-j)*10^j.at n=23A038228
• Triangle whose (i,j)-th entry is binomial(i,j)*10^(i-j)*3^j.at n=25A038305
• Numbers k such that, in the prime factorization of k, the product of exponents equals the product of prime factors.at n=20A054412
• Numbers whose 3 prime powers are a permutation of each other. Numbers with 3 distinct prime factors whose 3 exponents are a permutation of the 3 bases.at n=3A113620
• Numbers of the form Product_i b_i^e_i, where the b_i are all distinct values > 1 and the e_i are a permutation of the b_i.at n=29A122405
• Numbers of the form Product_i p_i^e_i, where the p_i are distinct primes and the e_i are a permutation of the p_i.at n=14A122406
• Totally multiplicative sequence with a(p) = 7p+1 for prime p.at n=39A166665
• Triangular matrix T where column 0 of T^m equals C(m*3^(n-1), n) at row n for n>=0, m>=0.at n=11A179430
• Column 1 of triangle A179430.at n=3A179433
• Floor[1/{(3+n^4)^(1/4)}], where {}=fractional part.at n=44A184538
• Numbers with prime factorization p^2*q^3*r^5 where p, q, and r are distinct primes.at n=7A190470
• Number of ways of writing n as the sum of 9 triangular numbers.at n=31A226253
• Size of complete unitary aperiodic semigroup with n states.at n=6A236409
• a(n) = largest k such that A049820(k) <= A262509(n).at n=22A263083
• Numbers such that (sum + product) of all their prime factors equals (sum + product) of all exponents in their prime factorization.at n=22A272818
• Numbers m such that Product(1 + p_i) = Product(1 + e_i), where m = Product((p_i)^e_i).at n=25A272858
• Numbers m such that sigma(Product(p_j)) = sigma(Product(e_j)), where m = Product((p_i)^e_i) and sigma = A000203.at n=23A272859
• a(n) = 378*n^2 - 54*n (n>=1).at n=17A305070
• Consider coefficients U(m,L,k) defined by the identity Sum_{k=1..L} Sum_{j=0..m} A302971(m,j)/A304042(m,j) * k^j * (T-k)^j = Sum_{k=0..m} (-1)^(m-k) * U(m,L,k) * T^k that holds for all positive integers L,m,T. This sequence gives 3-column table read by rows, where the n-th row lists coefficients U(2,n,k) for k = 0, 1, 2; n >= 1.at n=25A316349