212625

Appears in sequences

• Odd numbers divisible by exactly 9 primes (counted with multiplicity).at n=24A046322
• a(n) = Product_{k=1..n} (2*k-1)^(2*n-2*k+1).at n=3A136411
• G.f.: -x*(x-1)*(1+x)/(1-x-7*x^2-x^3+x^4).at n=12A171064
• Number of distinct (unordered) pairs of partitions of a 10-element set that have Rand distance n.at n=31A192103
• Numbers having factorization Product_{i=1..m} p(i)^e(i) such that m > 1 and p(i) + e(i) is the same for each i.at n=29A219302
• Number of maximal matchings in the n-triangular honeycomb rook graph.at n=6A289900
• Triangle read by rows: T(n, k) = (k+1)*S2(n+1, k+1), for n >= k >= 0, and S2 = A048993 (Stirling2).at n=49A321331
• Squared area of quadrilateral with sides prime(n), prime(n+1), prime(n+2), prime(n+3) of odd primes configured as a cyclic quadrilateral. Sequence index starts at n=2 to omit the even prime.at n=5A330496
• Positive integers k = p_1^e_1*p_2^e_2*p_3^e_3, such that the points (p_1, e_1), (p_2, e_2) and (p_3, e_3) lie on a straight line with nonzero slope.at n=14A389340