a(n) = (2^0)*(2^1)*(2^2)*(2^3)...(2^n)-1 = 2^T(n) - 1 where T(n) = A000217(n) is the n-th triangular number.
A126883
a(n) = (2^0)*(2^1)*(2^2)*(2^3)...(2^n)-1 = 2^T(n) - 1 where T(n) = A000217(n) is the n-th triangular number.
Terms
- a(0) =0a(1) =1a(2) =7a(3) =63a(4) =1023a(5) =32767a(6) =2097151a(7) =268435455a(8) =68719476735
External references
- oeis: A126883