65590

Appears in sequences

• Number of complete compositions of n.at n=17A107429
• Number of Carmichael numbers (A002997) less than 2^n.at n=47A225005
• a(0) = 4; to obtain a(k), write out the base-(2^k) expansion of a(k-1), bump to base 2^(k+1), then subtract 1.at n=14A372237