39039

Appears in sequences

• Expansion of 1/((1-x)(1-3x)(1-5x)(1-11x)).at n=4A021474
• Number of nonempty subsets of {1,2,...,n} in which exactly 1/6 of the elements are <= n/2.at n=25A047169
• Number of nonempty subsets of {1,2,...,n} in which exactly 5/6 of the elements are <= n/2.at n=25A047170
• a(n) = A028321(n)/2.at n=26A051473
• Sum of the prime factors of k equals half the sum of the prime factors of k + 1.at n=18A074213
• Triangle of coefficients, read by rows, where T(n,k) is the coefficient of x^n*y^k in f(x,y) that satisfies f(x,y) = 1/(1-x) - x^2/(1-x)^3 + xy*f(x,y)^3.at n=41A086632
• a(n) = Fibonacci(n)*n*binomial(2*n,n)/(n+1).at n=7A119697
• Number of 2143-avoiding Dumont paths of the 2nd kind of length 2n.at n=9A123922
• Positions of hexagonal pyramidal numbers in the EKG sequence.at n=38A144080
• Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, 0, 0), (-1, 0, 1), (0, -1, 0), (0, 1, -1), (1, 0, 1)}.at n=9A149356
• Integers of the form A164577(k)/3.at n=37A164619
• Successive integers produced by Conway's PRIMEGAME using Kilminster's Fractran program with only nine fractions.at n=19A183132
• 13 times hexagonal numbers: a(n) = 13*n*(2*n-1).at n=39A194713
• Number of (w,x,y) with all terms in {0,...,n} and w>floor((x+y)/3).at n=38A212974
• Convolution of the even-indexed triangular numbers (A014105) and the squares (A000290).at n=14A277228
• Numbers m such that there are precisely 17 groups of order m.at n=17A294949
• Denominator of series expansion of the hypergeometric series 3F2([1/2, 1, 1], [3/2, 3/2], x).at n=6A321234