73710

Appears in sequences

• sigma_3(n): sum of cubes of divisors of n.at n=39A001158
• Theta series of E_6 lattice.at n=32A004007
• a(n) = T(2n,n+1), where T is the array in A026300.at n=7A026306
• Sum of n-th powers of divisors of 40.at n=3A034667
• a(0)=1, a(n) = sigma_3(2n).at n=20A091986
• a(n) = sigma_3(3n+1).at n=13A092342
• Numbers with prime factorization p*q*r*s*t^4 (where p, q, r, s, t are distinct primes).at n=21A190110
• q-expansion of modular form psi_0^4/t_{3B}.at n=40A198956
• Number of n X 4 0..1 arrays avoiding 0 0 1 and 1 0 0 horizontally and 0 0 1 and 1 0 1 vertically.at n=19A209646
• Numbers k with the property that if the base-8 representation of k is read backwards, the result is an integral multiple of k.at n=15A223090
• Number T(n,k) of endofunctions on [n] with all cycles of length k; triangle T(n,k), n>=0, 0<=k<=n, read by rows.at n=31A243098
• Expansion of exp( Sum_{n>=1} -sigma(9*n)*x^n/n ) in powers of x.at n=20A283169
• Irregular triangle read by rows: T(n,m) = number of lattice paths of type {A^Q}_R terminating at point (n, m).at n=55A291082
• Triangular array read by rows: row n shows the coefficients of the polynomial p(x,n) constructed as in Comments; these polynomials form a strong divisibility sequence.at n=32A328644
• a(n)/n! is the maximum absolute value of the entries of the inverse of the Vandermonde matrix with entries 0,1,2,..., n-1.at n=6A335786
• Nonunitary near-perfect numbers: k such that nusigma(k) = k + d where d is a nonunitary divisor of k.at n=29A362969
• Triangle T(n, k) read by rows: T(n, k) = 2^n*binomial(2*n + 1, 2*k + 1) * Pochhammer(1/2, n - k) * Pochhammer(1/2, k).at n=26A380281