186497

Appears in sequences

• a(n) = floor(n*(n-1)*(n-2)*(n-3)/21).at n=46A011931
• Strong pseudoprimes to base 15.at n=21A020241
• Strong pseudoprimes to base 43.at n=35A020269
• Decompose the multiplicative group of integers modulo N as a product of cyclic groups C_{k_1} x C_{k_2} x ... x C_{k_m}, where k_i divides k_j for i < j, then a(n) is the smallest N such that the product contains a copy of C_{2n}.at n=46A302099
• a(n) is the smallest k such that the p-rank of (Z/kZ)* is 2, where p = prime(n) and (Z/kZ)* is the multiplicative group of integers modulo n.at n=14A307434