550540

Appears in sequences

• Numbers k such that 1+k, 1+k^2, 1+k^4 and 1+k^16 are all prime.at n=17A188698
• G.f.: Sum_{k>=1} x^(2*k-1)/(1-x^(2*k-1)) * Product_{k>=1} (1+x^k)/(1-x^k).at n=30A305105