Number of compositions of n such that the number of parts and the largest part and the smallest part are pairwise coprime.

A199890

Number of compositions of n such that the number of parts and the largest part and the smallest part are pairwise coprime.

Terms

    a(0) =1a(1) =1a(2) =1a(3) =6a(4) =4a(5) =15a(6) =37a(7) =81a(8) =133a(9) =270a(10) =565a(11) =1200a(12) =2449a(13) =4961a(14) =10014a(15) =20083a(16) =39585a(17) =77566a(18) =152934a(19) =305587a(20) =617857a(21) =1257333a(22) =2558837a(23) =5180712a(24) =10404918a(25) =20732162a(26) =41087390a(27) =81291644a(28) =161136101a(29) =320733232

External references