54741

Appears in sequences

• a(n) = (3 + 2*n + 6*n^2 + 4*n^3)/3.at n=34A166464
• Composite numbers k of the form 4u+1 for which the odd part of phi(k) divides k-1.at n=26A339870
• Intersection of A137409 and A339870: Composite numbers k of the form 4u+1 having more than one prime factor of type 4u+3, and for which the odd part of phi(k) divides k-1.at n=6A339875