24270

Appears in sequences

• Cototient of the n-th primorial number.at n=5A053144
• Triangle T(n,k) = ((-1)^(n+k)/(n+1))*Sum_{j=0..n} (-1)^j*j!*Stirling2(n, j)* binomial(n-j, k)*binomial(n+j, j), read by rows.at n=26A156653
• Lower Wythoff values for sequence A185615(n).at n=26A185616
• Numbers k such that k^2 +/- (k-1) and (k-1)*k^2 +/- 1 are all primes.at n=27A239326
• Number of (6+2)X(n+2) 0..4 arrays with every consecutive three elements in every row and diagonal having exactly two distinct values, and in every column and antidiagonal not having exactly two distinct values, and new values 0 upwards introduced in row major order.at n=9A252967
• Nonnegative integers n such that in balanced ternary representation the number of occurrences of each trit doubles when n is squared.at n=33A257867
• a(n) is the smallest k such that the following are four primes: prime(n)*k-1, prime(n)*k+1, prime(n)*k^2-1, prime(n)*k^2+1. Or -1 if no such k exists.at n=28A266239
• Square array A(n,k): number of integers having k or more factors less than prime(n+1) in their prime factorization, within any interval of primorial(n)^k positive integers.at n=34A281891
• Triangle of coefficients of quasi-Stirling polynomials.at n=23A331998