85800

Appears in sequences

• a(n) = 5*(n+1)*binomial(n+4,6).at n=7A027802
• a(n) = 30*(n+1)*binomial(n+4,10).at n=3A027806
• Numbers n such that n | Sigma_2(n) + Phi(n)^2.at n=9A055696
• Numbers k such that phi(prime(k) + 1) == 0 (mod k).at n=22A067732
• Nonnegative values x of solutions (x, y) to the Diophantine equation x^2+(x+2401)^2 = y^2.at n=21A118630
• Composite numbers such that the square root of the sum of squares of their prime factors is a prime.at n=29A134607
• Numbers with prime factorization p*q*r*s^2*t^3 (where p, q, r, s, t are distinct primes).at n=23A190111
• Number of (w,x,y,z) with all terms in {1,...,n} and |x-y|>=|y-z|.at n=20A212682
• Number A(n,k) of solid standard Young tableaux of shape [[(n)^(k+1)],[n]^k]; square array A(n,k), n>=0, k>=0, read by antidiagonals.at n=17A214631
• Square array read by antidiagonals arising in the enumeration of corners.at n=24A259101
• a(n) = 4*(n + 1)*(n + 2)*(4*n + 3)/3.at n=24A267522
• Triangle read by rows, Lah numbers of order 2, T(n,n) = 1, T(n,k) = 0 if k<0 or k>n, otherwise T(n,k) = T(n-1,k-1)+((n-1)^2+k^2)*T(n-1,k), for n>=0 and 0<=k<=n.at n=23A268434
• Least number, m, such that m^2 is expressible in just n ways as (p+1)(q+1) where p and q are distinct primes.at n=51A274877