1782144

Appears in sequences

• a(n) = (1/(1!*2!*3!*4!))*Sum_{1 <= x_1, x_2, x_3, x_4 <= n} |det V(x_1,x_2,x_3,x_4)|, where V(x_1,x_2,x_3,x_4) is the Vandermonde matrix of order 4.at n=14A133111
• a(n) = n*(n+1)*(n+2)*(n+3)*(n+4)*(n+5)/5.at n=12A162669
• Numbers k for which sigma(k)/k - 3/4 is an integer.at n=3A218405
• Numbers k such that sigma(k) mod k = antisigma(k) mod k, where sigma(k) = A000203(k) = sum of divisors of k, antisigma(k) = A024816(k) = sum of non-divisors of k.at n=11A229088