Number of compositions of n where the gcd of the parts equals the median of the parts.

Terms

a(0) =1a(1) =2a(2) =4a(3) =8a(4) =11a(5) =26a(6) =44a(7) =89a(8) =165a(9) =337a(10) =638a(11) =1292a(12) =2521a(13) =5044a(14) =9931a(15) =19859a(16) =39355a(17) =78462a(18) =155970a(19) =311161a(20) =619221a(21) =1234838a(22) =2460906a(23) =4907970a(24) =9785136a(25) =19521409a(26) =38938072a(27) =77691126a(28) =155017553a(29) =309366167