1048320

Appears in sequences

• a(n) = 2^n * (3n)! / (2n+1)!.at n=5A014298
• E.g.f. ( 1-x-sqrt(1-2*x+x^2-4*x^3) )/(2*x^2).at n=8A052743
• Number of periodic palindromes using exactly six different symbols.at n=15A056492
• Number of primitive (period n) periodic palindromes using exactly six different symbols.at n=15A056502
• Largest number of binary size n (i.e., between (n-1)-th and n-th powers of 2) with the following property: cube of its number of divisors is larger than the number itself.at n=19A056767
• Numbers whose set of base 16 digits is {0,F}, where F base 16 = 15 base 10.at n=28A097262
• Product ceiling(n/1)*ceiling(n/2)*ceiling(n/3)*...*ceiling(n/n) (the 'ceiling factorial').at n=13A131385
• Numbers that can be written as (a^2-1)(b^2-1) in three or more distinct ways.at n=13A134856
• Numbers that can be written as (a^2-1)(b^2-1) in four or more distinct ways.at n=1A134857
• a(n) = n^5 - n^2.at n=16A135497
• If an array is made of columns of -nacci sequences, fibo-, tribo- etc. all starting w. 1,1,2 etc, the NW to SE diagonals can be extended by computation. The above is diagonal 9. See A159741 for details.at n=12A159746
• Sums of adjacent amicable numbers, a(n) = A063990(2n-1) + A063990(2n).at n=29A161005
• 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=41A172106
• The sum of the two numbers in an amicable pair, A002025(n) + A002046(n).at n=29A180164
• Fibonacci 14-step numbers, a(n) = a(n-1) + a(n-2) + ... + a(n-14).at n=21A220469
• Sum of neighbor maps: number of nX4 binary arrays indicating the locations of corresponding elements equal to the sum mod 3 of their horizontal and antidiagonal neighbors in a random 0..2 nX4 array.at n=4A222383
• T(n,k)=Sum of neighbor maps: number of nXk binary arrays indicating the locations of corresponding elements equal to the sum mod 3 of their horizontal and antidiagonal neighbors in a random 0..2 nXk array.at n=32A222386
• Triangle S(n,k) by rows: coefficients of 3^((n-1)/2)*(x^(1/3)*d/dx)^n when n is odd, and of 3^(n/2)*(x^(2/3)*d/dx)^n when n is even.at n=42A223169
• Triangle S(n,k) by rows: coefficients of 3^(n/2)*(x^(2/3)*d/dx)^n when n=0,2,4,6,...at n=22A223526
• Number of ordered pairs of permutation functions on n elements satisfying f(f(x)) = g(f(g(x))).at n=8A239837