a(n) = Sum_{k=0..12} binomial(n,k).

Terms

a(0) =1a(1) =2a(2) =4a(3) =8a(4) =16a(5) =32a(6) =64a(7) =128a(8) =256a(9) =512a(10) =1024a(11) =2048a(12) =4096a(13) =8191a(14) =16369a(15) =32647a(16) =64839a(17) =127858a(18) =249528a(19) =480492a(20) =910596a(21) =1695222a(22) =3096514a(23) =5546382a(24) =9740686a(25) =16777216a(26) =28354132a(27) =47050564a(28) =76717268a(29) =123012781