148176

Appears in sequences

• Number of ways of placing non-attacking knights on an n X n chessboard symmetric under horizontal reflection.at n=7A129894
• If (a_n) is a sequence then let L(a_n)=(b_n) where b_n = a_n^2 - a_{n-1} a_{n+1}. The given sequence is the rows of the triangle obtained by computing L^2(binomial(n,k)).at n=30A140982
• a(n) = floor(1/{(2+n^4)^(1/4)}), where {} = fractional part.at n=42A184537
• Triangle a(n,k) = binomial(n,k)*binomial(n+1,k+1)*binomial(n+2,k+2) read by rows.at n=30A187552
• Numbers with prime factorization p^3*q^3*r^4 where p, q, and r are distinct primes.at n=3A190472
• Molecular topological indices of the Moebius ladders.at n=35A192833
• a(n) = Product_{d|n} (tau(d)*pod(d)) where tau(k) = the number of divisors of k (A000005) and pod(k) = the product of the divisors of k (A007955).at n=20A307101
• a(n) = lcm(sigma(n), pod(n)) / n, where sigma (k) = the sum of divisors of k (A000203) and pod(n) = the product of divisors of k (A007955).at n=41A307893
• a(n) = Product_{d|n} lcm(tau(d), pod(d)) where tau(k) is the number of divisors of k (A000005) and pod(k) is the product of divisors of k (A007955).at n=20A334807
• Numbers k such that k and the next two numbers after k with the same prime signature as k also have the same set of distinct prime divisors as k.at n=4A340303
• Numbers of multiplicative persistence 4 which are themselves the product of digits of a number.at n=28A350183
• Product of the divisors of n whose arithmetic derivative is odd.at n=41A353975
• Triangular array read by rows. T(n,k) is the number of Green's H-classes of rank k in the semigroup of partial transformations, n >= 0, 0 <= k <= n.at n=41A363849
• Numbers k for which k^2 + (k')^2 is a square, where k' is the arithmetic derivative of k (A003415).at n=39A365850
• Cubefull numbers whose number of coreful divisors is divisible by their number of exponential divisors.at n=35A382064
• Cubefull numbers with more than 2 distinct prime factors.at n=6A391755