Number of compositions of n such that the number of parts and the largest part and the smallest part are pairwise not coprime.
A199891
Number of compositions of n such that the number of parts and the largest part and the smallest part are pairwise not coprime.
Terms
- a(0) =0a(1) =0a(2) =0a(3) =1a(4) =0a(5) =2a(6) =0a(7) =4a(8) =1a(9) =8a(10) =12a(11) =31a(12) =30a(13) =50a(14) =84a(15) =166a(16) =240a(17) =367a(18) =560a(19) =970a(20) =1647a(21) =2736a(22) =4340a(23) =6924a(24) =11185a(25) =18334a(26) =29875a(27) =48272a(28) =77632a(29) =125262
External references
- oeis: A199891