Number of compositions of 7*n-6 into parts 1 and 7.

Terms

a(0) =1a(1) =3a(2) =13a(3) =66a(4) =330a(5) =1624a(6) =7973a(7) =39173a(8) =192539a(9) =946375a(10) =4651541a(11) =22862658a(12) =112371609a(13) =552314945a(14) =2714670141a(15) =13342810843a(16) =65580931949a(17) =322335276473