39930

Appears in sequences

• Number of permutations satisfying -k<=p(i)-i<=r and p(i)-i not in I, i=1..n, with k=2, r=3, I={2}.at n=14A080009
• Ordered m for which m = k^3*a*b*(a^4 - b^4) determine (unique) solution triples(k,a,b), where k=1,2,3,... and (a,b) are coprime pairs, not both odd (i.e., of opposite parity).at n=25A081779
• Number of compositions into a prime number of distinct parts.at n=31A102623
• a(n) = if n mod 2 = 1 then (n^2-1)*n^3/4 else n^5/4.at n=11A122657
• a(n) = ((n-th prime)^5-(n-th prime)^3)/4.at n=4A138434
• G.f.: A(x) = exp( Sum_{n>=1} 2^n * x^n/(n*(1+x^n)) ).at n=16A165941
• Number of (w,x,y,z) with all terms in {1,...,n} and w<2x and y>2z.at n=22A212504
• Number of subsets of {1,2,...,n} such that no two elements differ by 2, 4, or 5.at n=29A375983
• Integers k such that k = Sum k/(p_i + j), where p_i are the prime factors of k (with multiplicity). Case j = 1.at n=31A380889