28083

Appears in sequences

• Numbers having four 6's in base 8.at n=27A043448
• Numbers n such that sum of distinct primes dividing n is divisible by the largest prime dividing n. Also n is neither a prime, nor a true power of prime and n is squarefree. Squarefree solutions of A071140.at n=29A071141
• Numbers n such that (i) the sum of the distinct primes dividing n is divisible by the largest prime dividing n and (ii) n has exactly 4 distinct prime factors and (iii) n is squarefree.at n=11A071143
• Squarefree numbers k such that the largest prime factor of k is equal to the sum of the other prime factors of k.at n=28A071312
• Expansion of f(-q)^2 * Q(q) in powers of q.at n=14A122266
• Expansion of (psi(-x) * phi(x)^4)^2 in powers of x where phi(), psi() are Ramanujan theta functions.at n=42A209942
• Expansion of (psi(x) * phi(-x)^4)^2 in powers of x where phi(), psi() are Ramanujan theta functions.at n=42A215472
• Numbers n such that the sum of the distinct prime divisors of n that are congruent to 1 mod 4 equals the sum of the distinct prime divisors congruent to 3 mod 4.at n=15A215949
• Consider the spiral of Theodorus (A072895). This sequence gives the number of k successive triangles which is closer to 360 degrees than any previous k triangles.at n=7A224269
• Expansion of g.f. 1/ (1-x^1*(1-x^(m+1))/ (1-x^2*(1-x^(m+2))/ (1- ... ))) for m=6.at n=21A228646
• Expansion of f(-q^3)^2 * Q(q^3) + 48 * q * f(-q^3)^10 in powers of q.at n=42A234565
• Number T(n,k) of set partitions of [n] such that the maximal value of all absolute differences between least elements of consecutive blocks and between consecutive elements within the blocks equals k; triangle T(n,k), n>=0, 0<=k<=max(n-1,0), read by rows.at n=51A287416
• Number of involutions of [n] having exactly one peak.at n=23A303649
• G.f. A(x) satisfies: 1/(1 - x) = A(x)*A(x^2)^2*A(x^3)^3*A(x^4)^4* ... *A(x^k)^k* ...at n=36A307648
• Number of multiset partitions of integer partitions of n where all parts have the same product.at n=32A320886
• Numbers k such that omega(k) = 4 and the largest prime factor of k equals the sum of its remaining distinct prime factors, where omega(k) = A001221(k).at n=14A383728