1234800

Appears in sequences

• Triangle of labeled mobiles (circular rooted trees) with n nodes and k leaves.at n=31A055349
• Number of labeled mobiles (circular rooted trees) with n nodes and 4 leaves.at n=3A055351
• a(n) is the smallest number representable in exactly n ways as a sum of 2 powerful(1) numbers.at n=34A115354
• Triangle of denominators of the cube of a certain lower triangular matrix.at n=21A119932
• Triangle of denominators of the cube of a certain lower triangular matrix.at n=22A119932
• Triangle of denominators of the cube of a certain lower triangular matrix.at n=23A119932
• Triangle of denominators of the cube of a certain lower triangular matrix.at n=24A119932
• Least common multiple (LCM) of denominators of the rows of the triangle of rationals A119935/A119932.at n=6A119936
• The triangle T_2(n, m), where T_2(n, m) is the number of surjective multi-valued functions from {1, 1, 2, 3, ..., n-1} to {1, 2, 3, ..., m} by rows (n >= 1, 1 <= m <= n).at n=42A172106
• a(n) is the number of solutions to the congruence Sum_{k=1..n} x_k == 1 (mod 2n), where x_k are distinct elements of the set {0, 1, ..., 2n}, k = 1..n.at n=6A174663
• Reversing the exponents order in the prime factorization of n a different number with the same digits of n is obtained.at n=7A224253
• Numerator of the harmonic mean of the first n squares.at n=6A246498
• Triangle read by rows: T(n,k) (n >= 1, 4 <= k <= n+3) is the number of k-sequences of balls colored with at most n colors such that exactly four balls are the same color as some other ball in the sequence.at n=25A292999
• Triangular array read by rows. T(n,k) is the number of sets of lists (as in A000262(n)) with exactly k size 2 lists, n >= 0, 0 <= k <= floor(n/2).at n=33A351823
• a(n) is the least number that has exactly n exponential abundant divisors.at n=18A389299
• Primitives exponential abundant numbers that are not primitives exponential unitary abundant.at n=10A391086
• Primitive exponential Zumkeller numbers that are not primitive exponential unitary Zumkeller numbers.at n=11A391091